CBQE-0: change priority of test case

Change-Id: Ib8e0b30b97d0fee798260735da81cd95039518eb
Reviewed-on: http://review.couchbase.org/37681
Reviewed-by: Parag Agarwal <agarwal.parag@gmail.com>
Tested-by: Parag Agarwal <agarwal.parag@gmail.com>