minor #5378 [Cookbook][Controller] use the jinja lexer to render Twig code (xabbuh)

This PR was merged into the 2.3 branch.

Discussion
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[Cookbook][Controller] use the jinja lexer to render Twig code

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no
| Applies to    | all
| Fixed tickets |

Using `twig` works on newer Sphinx versions, but makes it harder for people to build the documentation locally with older versions.

Commits
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52316ac use the jinja lexer to render Twig code

Author: xabbuh

cookbook/controller/error_pages.rst

@@ -136,7 +136,7 @@ The cause of this problem is that routing is done before security. If a 404 erro
 occurs, the security layer isn't loaded and thus, the ``is_granted()`` function
 is undefined. The solution is to add the following check before using this function:
 
-.. code-block:: twig
+.. code-block:: jinja
 
     {% if app.user and is_granted('...') %}
         {# ... #}