fix logs in _get_and_parse_builds

Change-Id: I7365f829e26f764c6f1360027d83eb33c8aeb347
Reviewed-on: http://review.couchbase.org/30257
Reviewed-by: Andrei Baranouski <andrei.baranouski@gmail.com>
Tested-by: Andrei Baranouski <andrei.baranouski@gmail.com>