After running standalone.sh from this zip file: http://download.eng.bos.redhat.com/devel/candidates/jboss/sso/JBSSO-7.1.0-DR1/rh-sso-7.1.0.DR1.zip
exception is thrown with stacktrace below:

12:44:19,414 WARN [org.jboss.modules] (ServerService Thread Pool – 46) Failed to define class org.keycloak.authorization.policy.provider.drools.DroolsPolicyProviderFactory in Module "org.keycloak.keycloak-authz-policy-drools:main" from local module loader @42f30e0a (finder: local module finder @24273305 (roots: /home/mhajas/Work/java/manual-testing/filter/rh-sso-7.1/modules,/home/mhajas/Work/java/manual-testing/filter/rh-sso-7.1/modules/system/layers/keycloak,/home/mhajas/Work/java/manual-testing/filter/rh-sso-7.1/modules/system/layers/base)): org.jboss.modules.ModuleLoadError: org.drools:main
at org.jboss.modules.ModuleLoadException.toError(ModuleLoadException.java:74)
at org.jboss.modules.Module.getPathsUnchecked(Module.java:1434)
at org.jboss.modules.Module.loadModuleClass(Module.java:600)
at org.jboss.modules.ModuleClassLoader.findClass(ModuleClassLoader.java:190)
at org.jboss.modules.ConcurrentClassLoader.performLoadClassUnchecked(ConcurrentClassLoader.java:363)
at org.jboss.modules.ConcurrentClassLoader.performLoadClass(ConcurrentClassLoader.java:351)
at org.jboss.modules.ConcurrentClassLoader.loadClass(ConcurrentClassLoader.java:93)
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:760)
at org.jboss.modules.ModuleClassLoader.doDefineOrLoadClass(ModuleClassLoader.java:358)
at org.jboss.modules.ModuleClassLoader.defineClass(ModuleClassLoader.java:437)
at org.jboss.modules.ModuleClassLoader.loadClassLocal(ModuleClassLoader.java:274)
at org.jboss.modules.ModuleClassLoader$1.loadClassLocal(ModuleClassLoader.java:78)
at org.jboss.modules.Module.loadModuleClass(Module.java:605)
at org.jboss.modules.ModuleClassLoader.findClass(ModuleClassLoader.java:190)
at org.jboss.modules.ConcurrentClassLoader.performLoadClassUnchecked(ConcurrentClassLoader.java:363)
at org.jboss.modules.ConcurrentClassLoader.performLoadClass(ConcurrentClassLoader.java:351)
at org.jboss.modules.ConcurrentClassLoader.loadClass(ConcurrentClassLoader.java:93)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:348)
at java.util.ServiceLoader$LazyIterator.nextService(ServiceLoader.java:370)
at java.util.ServiceLoader$LazyIterator.next(ServiceLoader.java:404)
at java.util.ServiceLoader$1.next(ServiceLoader.java:480)
at org.keycloak.provider.DefaultProviderLoader.load(DefaultProviderLoader.java:47)
at org.keycloak.provider.ProviderManager.load(ProviderManager.java:88)
at org.keycloak.services.DefaultKeycloakSessionFactory.loadSPIs(DefaultKeycloakSessionFactory.java:110)
at org.keycloak.services.DefaultKeycloakSessionFactory.init(DefaultKeycloakSessionFactory.java:75)
at org.keycloak.services.resources.KeycloakApplication.createSessionFactory(KeycloakApplication.java:244)
at org.keycloak.services.resources.KeycloakApplication.<init>(KeycloakApplication.java:78)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:422)
at org.jboss.resteasy.core.ConstructorInjectorImpl.construct(ConstructorInjectorImpl.java:150)
at org.jboss.resteasy.spi.ResteasyProviderFactory.createProviderInstance(ResteasyProviderFactory.java:2209)
at org.jboss.resteasy.spi.ResteasyDeployment.createApplication(ResteasyDeployment.java:299)
at org.jboss.resteasy.spi.ResteasyDeployment.start(ResteasyDeployment.java:240)
at org.jboss.resteasy.plugins.server.servlet.ServletContainerDispatcher.init(ServletContainerDispatcher.java:113)
at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.init(HttpServletDispatcher.java:36)
at io.undertow.servlet.core.LifecyleInterceptorInvocation.proceed(LifecyleInterceptorInvocation.java:117)
at org.wildfly.extension.undertow.security.RunAsLifecycleInterceptor.init(RunAsLifecycleInterceptor.java:78)
at io.undertow.servlet.core.LifecyleInterceptorInvocation.proceed(LifecyleInterceptorInvocation.java:103)
at io.undertow.servlet.core.ManagedServlet$DefaultInstanceStrategy.start(ManagedServlet.java:239)
at io.undertow.servlet.core.ManagedServlet.createServlet(ManagedServlet.java:133)
at io.undertow.servlet.core.DeploymentManagerImpl.start(DeploymentManagerImpl.java:527)
at org.wildfly.extension.undertow.deployment.UndertowDeploymentService.startContext(UndertowDeploymentService.java:101)
at org.wildfly.extension.undertow.deployment.UndertowDeploymentService$1.run(UndertowDeploymentService.java:82)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
at org.jboss.threads.JBossThread.run(JBossThread.java:320)

12:44:19,419 ERROR [org.jboss.msc.service.fail] (ServerService Thread Pool – 46) MSC000001: Failed to start service jboss.undertow.deployment.default-server.default-host./auth: org.jboss.msc.service.StartException in service jboss.undertow.deployment.default-server.default-host./auth: java.lang.RuntimeException: RESTEASY003325: Failed to construct public org.keycloak.services.resources.KeycloakApplication(javax.servlet.ServletContext,org.jboss.resteasy.core.Dispatcher)
at org.wildfly.extension.undertow.deployment.UndertowDeploymentService$1.run(UndertowDeploymentService.java:85)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
at org.jboss.threads.JBossThread.run(JBossThread.java:320)
Caused by: java.lang.RuntimeException: RESTEASY003325: Failed to construct public org.keycloak.services.resources.KeycloakApplication(javax.servlet.ServletContext,org.jboss.resteasy.core.Dispatcher)
at org.jboss.resteasy.core.ConstructorInjectorImpl.construct(ConstructorInjectorImpl.java:162)
at org.jboss.resteasy.spi.ResteasyProviderFactory.createProviderInstance(ResteasyProviderFactory.java:2209)
at org.jboss.resteasy.spi.ResteasyDeployment.createApplication(ResteasyDeployment.java:299)
at org.jboss.resteasy.spi.ResteasyDeployment.start(ResteasyDeployment.java:240)
at org.jboss.resteasy.plugins.server.servlet.ServletContainerDispatcher.init(ServletContainerDispatcher.java:113)
at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.init(HttpServletDispatcher.java:36)
at io.undertow.servlet.core.LifecyleInterceptorInvocation.proceed(LifecyleInterceptorInvocation.java:117)
at org.wildfly.extension.undertow.security.RunAsLifecycleInterceptor.init(RunAsLifecycleInterceptor.java:78)
at io.undertow.servlet.core.LifecyleInterceptorInvocation.proceed(LifecyleInterceptorInvocation.java:103)
at io.undertow.servlet.core.ManagedServlet$DefaultInstanceStrategy.start(ManagedServlet.java:239)
at io.undertow.servlet.core.ManagedServlet.createServlet(ManagedServlet.java:133)
at io.undertow.servlet.core.DeploymentManagerImpl.start(DeploymentManagerImpl.java:527)
at org.wildfly.extension.undertow.deployment.UndertowDeploymentService.startContext(UndertowDeploymentService.java:101)
at org.wildfly.extension.undertow.deployment.UndertowDeploymentService$1.run(UndertowDeploymentService.java:82)
... 6 more
Caused by: org.jboss.modules.ModuleLoadError: org.drools:main
at org.jboss.modules.ModuleLoadException.toError(ModuleLoadException.java:74)
at org.jboss.modules.Module.getPathsUnchecked(Module.java:1434)
at org.jboss.modules.Module.loadModuleClass(Module.java:600)
at org.jboss.modules.ModuleClassLoader.findClass(ModuleClassLoader.java:190)
at org.jboss.modules.ConcurrentClassLoader.performLoadClassUnchecked(ConcurrentClassLoader.java:363)
at org.jboss.modules.ConcurrentClassLoader.performLoadClass(ConcurrentClassLoader.java:351)
at org.jboss.modules.ConcurrentClassLoader.loadClass(ConcurrentClassLoader.java:93)
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:760)
at org.jboss.modules.ModuleClassLoader.doDefineOrLoadClass(ModuleClassLoader.java:358)
at org.jboss.modules.ModuleClassLoader.defineClass(ModuleClassLoader.java:437)
at org.jboss.modules.ModuleClassLoader.loadClassLocal(ModuleClassLoader.java:274)
at org.jboss.modules.ModuleClassLoader$1.loadClassLocal(ModuleClassLoader.java:78)
at org.jboss.modules.Module.loadModuleClass(Module.java:605)
at org.jboss.modules.ModuleClassLoader.findClass(ModuleClassLoader.java:190)
at org.jboss.modules.ConcurrentClassLoader.performLoadClassUnchecked(ConcurrentClassLoader.java:363)
at org.jboss.modules.ConcurrentClassLoader.performLoadClass(ConcurrentClassLoader.java:351)
at org.jboss.modules.ConcurrentClassLoader.loadClass(ConcurrentClassLoader.java:93)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:348)
at java.util.ServiceLoader$LazyIterator.nextService(ServiceLoader.java:370)
at java.util.ServiceLoader$LazyIterator.next(ServiceLoader.java:404)
at java.util.ServiceLoader$1.next(ServiceLoader.java:480)
at org.keycloak.provider.DefaultProviderLoader.load(DefaultProviderLoader.java:47)
at org.keycloak.provider.ProviderManager.load(ProviderManager.java:88)
at org.keycloak.services.DefaultKeycloakSessionFactory.loadSPIs(DefaultKeycloakSessionFactory.java:110)
at org.keycloak.services.DefaultKeycloakSessionFactory.init(DefaultKeycloakSessionFactory.java:75)
at org.keycloak.services.resources.KeycloakApplication.createSessionFactory(KeycloakApplication.java:244)
at org.keycloak.services.resources.KeycloakApplication.<init>(KeycloakApplication.java:78)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:422)
at org.jboss.resteasy.core.ConstructorInjectorImpl.construct(ConstructorInjectorImpl.java:150)
... 19 more

12:44:19,423 ERROR [org.jboss.as.controller.management-operation] (Controller Boot Thread) WFLYCTL0013: Operation ("add") failed - address: ([("deployment" => "keycloak-server.war")]) - failure description: {"WFLYCTL0080: Failed services" => {"jboss.undertow.deployment.default-server.default-host./auth" => "org.jboss.msc.service.StartException in service jboss.undertow.deployment.default-server.default-host./auth: java.lang.RuntimeException: RESTEASY003325: Failed to construct public org.keycloak.services.resources.KeycloakApplication(javax.servlet.ServletContext,org.jboss.resteasy.core.Dispatcher)
Caused by: java.lang.RuntimeException: RESTEASY003325: Failed to construct public org.keycloak.services.resources.KeycloakApplication(javax.servlet.ServletContext,org.jboss.resteasy.core.Dispatcher)
Caused by: org.jboss.modules.ModuleLoadError: org.drools:main"}}