CBQE-0: removed 30s sleep from create buckets from XDCR tests as MB-9745 is resolved

Change-Id: I0687253f7d98d8f1d808063cb426ee54f46662cf
Reviewed-on: http://review.couchbase.org/32414
Reviewed-by: Sangharsh Agarwal <sangharsh.agarwal@globallogic.com>
Tested-by: Sangharsh Agarwal <sangharsh.agarwal@globallogic.com>