unit test fix for #3052 and #3053

@ahmetmircik 

As I track in the code (HazelcastInstance, LifecycleService, NodeEngine, ServiceManager and and all ManagedService implementations), there is no wait for in-safe state cluster. Just this line exist

~~~~
shutdownLatch.await(Math.min(30, node.groupProperties.GRACEFUL_SHUTDOWN_MAX_WAIT.getInteger()), TimeUnit.SECONDS);
~~~~

But I think, this doesn't guarantee that all cluster is in safe state after this wait.

But Maybe I am wrong and I may misunderstand of code :) 

For this reason, I added these waiting time and on going migration check code to be sure for safe cluster state in test environment.