Merge branch '4.4' into 5.0

* 4.4:
  Make it more obvious what the $handler is (refers to the next item in the docs)

Author: javiereguiluz

components/messenger.rst

@@ -83,10 +83,13 @@ are configured for you:
 Example::
 
     use App\Message\MyMessage;
+    use App\MessageHandler\MyMessageHandler;
     use Symfony\Component\Messenger\Handler\HandlersLocator;
     use Symfony\Component\Messenger\MessageBus;
     use Symfony\Component\Messenger\Middleware\HandleMessageMiddleware;
 
+    $handler = new MyMessageHandler();
+
     $bus = new MessageBus([
         new HandleMessageMiddleware(new HandlersLocator([
             MyMessage::class => [$handler],