MB-12672: update tests according to comments

Change-Id: I08d08f8e224b9cf89bfcf1f0447ee67dafd2b54f
Reviewed-on: http://review.couchbase.org/43325
Tested-by: buildbot <build@couchbase.com>
Reviewed-by: Iryna Mironava <irynamironava@yandex.ru>