minor #15376 Update templates.rst for PR symfony/symfony#41414 (dayallnash)

This PR was merged into the 5.4 branch.

Discussion
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Update templates.rst for PR symfony/symfony#41414

Update docs to provide info on potential new feature found here: symfony/symfony#41414

Commits
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3acf948 Update templates.rst

Author: javiereguiluz

templates.rst

@@ -513,6 +513,9 @@ provided by Symfony:
                 # the path of the template to render
                 template:  'static/privacy.html.twig'
 
+                # the status code to include in the response headers
+                statusCode: 200
+
                 # special options defined by Symfony to set the page cache
                 maxAge:    86400
                 sharedAge: 86400