minor #13952 Update experimental_authenticators.rst (Souhail-5)

This PR was merged into the 5.1 branch.

Discussion
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Update experimental_authenticators.rst

Fix the link for `PreAuthenticatedUserBadge` class

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Commits
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486a1fe Update experimental_authenticators.rst

Author: javiereguiluz

security/experimental_authenticators.rst

@@ -464,7 +464,7 @@ the following badges are supported:
     authentication. The constructor requires a token ID (unique per form)
     and CSRF token (unique per request). See :doc:`/security/csrf`.
 
-:class:`Symfony\\Component\\Security\\Http\\Authenticator\\Passport\\Badge\\PreAuthenticatedBadge`
+:class:`Symfony\\Component\\Security\\Http\\Authenticator\\Passport\\Badge\\PreAuthenticatedUserBadge`
     Indicates that this user was pre-authenticated (i.e. before Symfony was
     initiated). This skips the
     :doc:`pre-authentication user checker </security/user_checkers>`.