CBQE-0 :: fix failing test case when port changes during rebalance+failover

Change-Id: Ic945493820a59e67d6a2d7c634c55bf0d4473fef
Reviewed-on: http://review.couchbase.org/41258
Reviewed-by: Parag Agarwal <agarwal.parag@gmail.com>
Tested-by: Parag Agarwal <agarwal.parag@gmail.com>