CBQE-1737: Fix Auto-failover test cases

Change-Id: I608fef9276ab429c5c8101788dd7af872b079a66
Reviewed-on: http://review.couchbase.org/34786
Reviewed-by: Andrei Baranouski <andrei.baranouski@gmail.com>
Tested-by: Parag Agarwal <agarwal.parag@gmail.com>