ISPN-4574 Fix StateTransferSuppressIT failure

The DefaultConsistentHash.toString() change in https://github.com/infinispan/infinispan/pull/2860 broke StateTransferSuppressIT.

Change RpcManagerImpl.getCommittedViewAsString and getPendingViewAsString
to return only the list of members.

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Reverse the operands to avoid negation maybe? Would look nicer.