minor symfony#13424 Adding path (ThomasLandauer)

This PR was squashed before being merged into the 3.4 branch.

Discussion
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Adding `path`

Please double-check the default value.

Commits
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9d6271a Adding `path`

Author: xabbuh

reference/configuration/security.rst

@@ -528,6 +528,14 @@ The user is considered to have changed when the user class implements
 required by the :class:`Symfony\\Component\\Security\\Core\\User\\UserInterface`
 (like the username, password or salt) changes.
 
+``path``
+~~~~~~~~
+
+**type**: ``string`` **default**: ``/logout``
+
+The path which triggers logout. If you change it from the default value ``/logout``,
+you need to set up a route with a matching path.
+
 ``success_handler``
 ~~~~~~~~~~~~~~~~~~~