bug #3435 Update custom_password_authenticator.rst (boardyuk)

This PR was merged into the 2.4 branch.

Discussion
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Update custom_password_authenticator.rst

Fixed TokenInterface use statement which was causing a "FatalErrorException: Compile Error:" to occur

Commits
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4101d9b Update custom_password_authenticator.rst

Author: weaverryan

Diff for: cookbook/security/custom_password_authenticator.rst

@@ -25,7 +25,7 @@ the user::
 
     use Symfony\Component\HttpFoundation\Request;
     use Symfony\Component\Security\Core\Authentication\SimpleFormAuthenticatorInterface;
-    use Symfony\Component\Security\Core\Authentication\TokenInterface;
+    use Symfony\Component\Security\Core\Authentication\Token\TokenInterface;
     use Symfony\Component\Security\Core\Authentication\Token\UsernamePasswordToken;
     use Symfony\Component\Security\Core\Encoder\EncoderFactoryInterface;
     use Symfony\Component\Security\Core\Exception\AuthenticationException;