Use useAttributeAsKey before the prototype method

Author: MattKetmo

components/config/definition.rst

@@ -149,8 +149,8 @@ An example of this:
         ->arrayNode('parameters')
             ->isRequired()
             ->requiresAtLeastOneElement()
+            ->useAttributeAsKey('name')
             ->prototype('array')
-                ->useAttributeAsKey('name')
                 ->children()
                     ->scalarNode('name')->isRequired()->end()
                     ->scalarNode('value')->isRequired()->end()