tests to use IsAllowed instead of deprecated cbauth helpers
tests to use IsAllowed instead of deprecated cbauth helpers

Change-Id: I28429a0ba973449e6b2eced343669b81f897ce6c
Reviewed-on: http://review.couchbase.org/62720
Tested-by: Artem Stemkovski <15a0730a27c69f62ab86f2b6c639fca202166c02@couchbase.com>
Reviewed-by: Aliaksey Artamonau <3c875bcfb3adf2a65b2ae7686ca921e6c9433147@gmail.com>

couchbase/cbauth,couchbase/cbauth