minor #10037 render versionadded directive outside the code block (xabbuh)

This PR was merged into the 3.4 branch.

Discussion
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render versionadded directive outside the code block

Commits
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04560be render versionadded directive outside the code block

Author: xabbuh

templating/twig_extension.rst

@@ -134,8 +134,8 @@ previous ``priceFilter()`` method::
         }
     }
 
- .. versionadded:: 3.4
-     The ``RuntimeExtensionInterface`` was introduced in Symfony 3.4.
+.. versionadded:: 3.4
+    The ``RuntimeExtensionInterface`` was introduced in Symfony 3.4.
 
 If you're using the default ``services.yaml`` configuration, this will already
 work! Otherwise, :ref:`create a service <service-container-creating-service>`