Improve the suspend-timeout test cases

Right now we are not covering all test cases available when we are using suspend-timeout attributes for the server lifecycle operations.

Discussions about the existing test cases concluded that we should be using the following strategy to test them effectively:

• A test case using suspend-timeout <0 -> We can unlock the web application manually. That means test the SuspendController.listeners.complete () event path.
• A test case using suspend-timeout> 0 -> We should not unlock manually the web application, and we should wait for the timeout, that means to test the SuspendController.listeners.timeout () event path.
• A test case using suspend-timeout = 0 -> That could become a redundant bit with the previous case because the event will be the SuspendController.listeners.timeout (), but we will not be included in the test that the event is fired as a result of a TimerTask ().

In order to allow the inflight tasks being stopped in our test suite, we need to change the way we are enabling Undertow in wildfly-core. Right now our TestSuspendServiceActivator is activating Undertow without using the IO worker threads, that means when the server is shutdown/stopped, the tasks created by Undertow are not automatically terminated.