minor #15744 [Twig] Add PHP Attributes to routing configuration example (sebpacz)

This PR was merged into the 5.3 branch.

Discussion
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[Twig] Add PHP Attributes to routing configuration example

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e1c8dd2 [Twig] Add PHP Attributes to routing configuration example

Author: javiereguiluz

templates.rst

@@ -216,6 +216,30 @@ Consider the following routing configuration:
             }
         }
 
+    .. code-block:: php-attributes
+
+        // src/Controller/BlogController.php
+        namespace App\Controller;
+
+        // ...
+        use Symfony\Component\HttpFoundation\Response;
+        use Symfony\Component\Routing\Annotation\Route;
+
+        class BlogController extends AbstractController
+        {
+            #[Route('/', name: 'blog_index')]
+            public function index(): Response
+            {
+                // ...
+            }
+
+            #[Route('/article/{slug}', name: 'blog_post')]
+            public function show(string $slug): Response
+            {
+                // ...
+            }
+        }
+
     .. code-block:: yaml
 
         # config/routes.yaml