Start tx in a new thread since {@link com.hazelcast.transaction.impl.TransactionImpl#THREAD_FLAG} is thread local
and during node shutdown thread flag does not cleared.
This is the reason of failures in repetitive test calls from same thread.
Merge branch 'master' of https://github.com/hazelcast/hazelcast
remove unneeded line
Merge pull request #3277 from ahmetmircik/fix/3.3/xaTest

Possible fix for test failure issue #3233: HazelcastXaTest.testRecovery