minor #5309 [Cookbook][Controller] few tweaks to the error pages article (xabbuh)

This PR was merged into the 2.3 branch.

Discussion
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[Cookbook][Controller] few tweaks to the error pages article

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

Commits
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c7d1266 few tweaks to the error pages article

Author: wouterj

cookbook/controller/error_pages.rst

@@ -46,7 +46,7 @@ is used to render a Twig template to show the user.
 
 .. _cookbook-error-pages-by-status-code:
 
-This controller uses the HTTP status code, request format and the following
+This controller uses the HTTP status code, the request format and the following
 logic to determine the template filename:
 
 #. Look for a template for the given format and status code (like ``error404.json.twig``
@@ -79,7 +79,7 @@ A typical project that returns HTML and JSON pages, might look like this:
                 ├─ error.html.twig      # All other HTML errors (including 500)
                 ├─ error404.json.twig
                 ├─ error403.json.twig
-                ├─ error.json.twig      # All other JSON errors (including 500)
+                └─ error.json.twig      # All other JSON errors (including 500)
 
 Example 404 Error Template
 --------------------------