Observability TCKs fail when -Dtestsuite.default.build.project.prefix=ee- is used

Switching to using standalone-microprofile.xml as the default config file used by test servers when the MP TCKs run broke the Dtestsuite.default.build.project.prefix=ee test setup that was part of WFLY-12985. (See recent https://ci.wildfly.org/viewType.html?buildTypeId=WF_MasterLinuxAltDistJdk8 results.). This is because the config/health/metrics/opentracing tcks will run against a server based on the ee-build output if that property is set, and those server's don't provide standalone-microprofile.xml.

Fix is to configure surefire/arquillian to use standalone.xml if that property is set.

The clustering testsuite fails as well, because the CLI script used to set up clustering tries to modify a non-existent standalone-microprofile-ha.xml. Solution there is separate that modification out into a separate script and only run it when needed.