Fix Xdebug mode default value

Author: ironex

images/php-fpm/php.ini

@@ -8,7 +8,7 @@ post_max_size = 100M
 max_input_vars = 10000
 
 [xdebug]
-xdebug.mode=debug
+xdebug.mode=off
 xdebug.client_host="host.docker.internal"
 xdebug.start_with_request=yes
 xdebug.discover_client_host = 1