Fix config/bundles.php

Author: smnandre

bundles/configuration.rst

@@ -482,7 +482,7 @@ namespace is then replaced with the XSD validation base path returned from
 method. This namespace is then followed by the rest of the path from the base
 path to the file itself.
 
-By convention, the XSD file lives in ``config/schema/``, but you
+By convention, the XSD file lives in ``config/schema/`` directory, but you
 can place it anywhere you like. You should return this path as the base path::
 
     // src/DependencyInjection/AcmeHelloExtension.php