ISPN-2608 & ISPN-2515: VersionedDistStateTransferTest and VersionedReplStateTransferTest are meant to check the cache state after the state transfer is complete

ISPN-2608 VersionedDistStateTransferTest intermittent failure 
ISPN-2515 VersionedReplStateTransferTest.testStateTransfer fails randomly

https://issues.jboss.org/browse/ISPN-2608
https://issues.jboss.org/browse/ISPN-2515

Wait for state transfer to end before checking the results