Update messenger.rst

Co-authored-by: Mata <[email protected]>

Author: sylfabre

messenger.rst

@@ -455,6 +455,7 @@ With the following code and configuration, messages will be dispatched like this
                 App\Message\SmsNotification: async_2
 
 .. code-block::php
+
     $messageBus->dispatch(new Notification());
     $messageBus->dispatch(new SmsNotification());