minor #17140 [Security] Minor: Deleting link (ThomasLandauer)

This PR was merged into the 5.4 branch.

Discussion
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[Security] Minor: Deleting link

The link text was wrong:

> See How to Write a Custom Authenticator below for a detailed look into the authentication process.

And passports are the next heading anyway.

Commits
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39536a1 Minor: Deleting link

Author: javiereguiluz

security/custom_authenticator.rst

@@ -143,9 +143,8 @@ The ``authenticate()`` method is the most important method of the
 authenticator. Its job is to extract credentials (e.g. username &
 password, or API tokens) from the ``Request`` object and transform these
 into a security
-:class:`Symfony\\Component\\Security\\Http\\Authenticator\\Passport\\Passport`.
-See :ref:`security-passport` below for a detailed look into the
-authentication process.
+:class:`Symfony\\Component\\Security\\Http\\Authenticator\\Passport\\Passport`
+(see below).
 
 After the authentication process finished, the user is either authenticated
 or there was something wrong (e.g. incorrect password). The authenticator