[Security] Add PHP Attribute example to controller

Author: wkania

security.rst

@@ -1089,6 +1089,24 @@ Next, you'll need to create a route for this URL (but not a controller):
             }
         }
 
+    .. code-block:: php-attributes
+
+        // src/Controller/SecurityController.php
+        namespace App\Controller;
+
+        use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
+        use Symfony\Component\Routing\Annotation\Route;
+
+        class SecurityController extends AbstractController
+        {
+            #[Route('/logout', name: 'app_logout', methods: ['GET'])]
+            public function logout()
+            {
+                // controller can be blank: it will never be executed!
+                throw new \Exception('Don\'t forget to activate logout in security.yaml');
+            }
+        }
+
     .. code-block:: yaml
 
         # config/routes.yaml