minor #11774 kernel.debug is a boolean, not a string (OskarStark)

This PR was merged into the 3.4 branch.

Discussion
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kernel.debug is a boolean, not a string

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Commits
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4d84a69 kernel.debug is a boolean, not a string

Author: OskarStark

reference/configuration/twig.rst

@@ -55,7 +55,7 @@ Configuration
 auto_reload
 ~~~~~~~~~~~
 
-**type**: ``boolean`` **default**: ``'%kernel.debug%'``
+**type**: ``boolean`` **default**: ``%kernel.debug%``
 
 If ``true``, whenever a template is rendered, Symfony checks first if its source
 code has changed since it was compiled. If it has changed, the template is
@@ -174,7 +174,7 @@ specific timezone is passed as argument.
 debug
 ~~~~~
 
-**type**: ``boolean`` **default**: ``'%kernel.debug%'``
+**type**: ``boolean`` **default**: ``%kernel.debug%``
 
 If ``true``, the compiled templates include a ``__toString()`` method that can
 be used to display their nodes.