Unify and adjust thread time outs

There are few place in Debezium code base, which already run tasks in parallel and use different timeouts (e.g. SHUTDOWN_WAIT_TIMEOUT in ChangeEventSourceCoordinator). Unify all these timeouts related to thread lifecycle, otherwise async engine may timeout while waiting for connector shutdown, while it is still waiting for another thread to shutdown.

Also, adjust the value the timeout in the test to that test don't fail randomly.