MB-11616: warning message during samples loading

Change-Id: Id08fbe7b5c8406006bde9510818964843cb51337
Reviewed-on: http://review.couchbase.org/39533
Reviewed-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
Tested-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>