The embedded host and server handlers hang on start

Recently we changed the way the EmbedHostControllerHandler and EmbedServerHandler wait for the embedded host/server until it starts.

We were using a pooling executing management operations to check the process state. We needed a different solution to be able to check the process state when the embedded host/server was launched with and empty configuration file.

In the new approach we exposed the process state to the client so it can be directly pooling without requiring a management operation.

Currently the update of this internal field is racy, and a hang can occurs starting the embedded.

We saw this bug in the CI test suite: https://ci.wildfly.org/viewLog.html?buildId=197876&buildTypeId=WF_MasterWindowsJdk12