CBQE-1245: ver tap client when TAP client is not used

bug automation of
MB-4460 seeing tap client activity even though the client is not using a TAP client

Change-Id: I57239119a5f482d6cb36850c000110af6739f4fa
Reviewed-on: http://review.couchbase.org/25931
Reviewed-by: Iryna Mironava <irynamironava@yandex.ru>
Tested-by: buildbot <build@couchbase.com>