Fixed xdebug guide

maxhelias · Maxime Helias · commit 1d1ec89a7fd4 · 2018-11-19T09:59:54.000+01:00
diff --git a/README.md b/README.md
@@ -58,7 +58,7 @@ As example, an override could look like this:
 version: '3.4'
 
 services:
-  php:
+  app:
     build:
       context: .
       target: symfony_docker_php_dev
