don't say we found multiple certificates when none was found

Change-Id: I74b3e5a297d3218fd78d23cf6ef7e2e418aac48c
Reviewed-on: http://review.couchbase.org/32375
Tested-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
Reviewed-by: Aliaksey Artamonau <aliaksiej.artamonau@gmail.com>