bug.pl: return with .bug

scripts/autorun/bug.pl

@@ -87,6 +87,7 @@ Irssi::signal_add 'event privmsg' => sub ($server, $data, $nick, $address) {
             $src = undef;
         }
         url_process($src, $on_info, $nick, $text, 1);
+        return;
     }
     unless (grep { uc($target) eq uc($_)} @channels) {
         return;