minor #11267 use App instead of AppBundle (OskarStark)

This PR was merged into the 4.2 branch.

Discussion
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use App instead of AppBundle

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Commits
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120dbaa use App instead of AppBundle

Author: javiereguiluz

doctrine/event_listeners_subscribers.rst

@@ -241,8 +241,8 @@ numbers mean that listeners are invoked earlier.
     .. code-block:: php
 
         // config/services.php
-        use AppBundle\EventListener\MyHighPriorityListener;
-        use AppBundle\EventListener\MyLowPriorityListener;
+        use App\EventListener\MyHighPriorityListener;
+        use App\EventListener\MyLowPriorityListener;
 
         $container
             ->autowire(MyHighPriorityListener::class)

reference/forms/types/entity.rst

@@ -286,7 +286,7 @@ This option allows you to move certain choices to the top of your list with a vi
 separator between them and the rest of the options. This option expects an array
 of entity objects::
 
-    use AppBundle\Entity\User;
+    use App\Entity\User;
     use Symfony\Bridge\Doctrine\Form\Type\EntityType;
     // ...
 

routing/optional_placeholders.rst

@@ -11,7 +11,7 @@ the available blog posts for this imaginary blog application:
 
     .. code-block:: php-annotations
 
-        // src/AppBundle/Controller/BlogController.php
+        // src/App/Controller/BlogController.php
         use Symfony\Component\Routing\Annotation\Route;
 
         // ...