CBQE-2340: fixing test by merging keys again after update/delete

Change-Id: Ibe4e3337663fa8e5c1fa9136a09604ec2a67c043
Reviewed-on: http://review.couchbase.org/40495
Reviewed-by: Sangharsh Agarwal <sangharsh.agarwal@globallogic.com>
Tested-by: Sangharsh Agarwal <sangharsh.agarwal@globallogic.com>