sslheaders AuTest: Skip if plugin does not exist#7681

bneradt merged 1 commit intoapache:8.1.xapache/trafficserver:8.1.xfrom

bneradt:cherry_pick_add_plugin_existence_check_for_sslheaders_autest_to_81xbneradt/trafficserver:cherry_pick_add_plugin_existence_check_for_sslheaders_autest_to_81xCopy head branch name to clipboard