CBQE-0: fix, cleanup was skipped in xdcr tests due to previous commit http://review.couchbase.org/#/c/37033/

Change-Id: I875153e2ccb806ce5218ac44fb54253d98876436
Reviewed-on: http://review.couchbase.org/37126
Reviewed-by: Sangharsh Agarwal <sangharsh.agarwal@globallogic.com>
Tested-by: Sangharsh Agarwal <sangharsh.agarwal@globallogic.com>