minor #17135 [Security] Adding info where login attempts are stored (ThomasLandauer)

This PR was squashed before being merged into the 5.4 branch.

Discussion
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[Security] Adding info where login attempts are stored

Commits
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7ad5d9f [Security] Adding info where login attempts are stored

Author: javiereguiluz

rate_limiter.rst

@@ -360,6 +360,8 @@ the :class:`Symfony\\Component\\RateLimiter\\Reservation` object returned by the
         }
     }
 
+.. _rate-limiter-storage:
+
 Storing Rate Limiter State
 --------------------------
 

security.rst

@@ -1462,6 +1462,10 @@ You must enable this using the ``login_throttling`` setting:
 
     The ``login_throttling.interval`` option was introduced in Symfony 5.3.
 
+Internally, Symfony uses the :doc:`Rate Limiter component </rate_limiter>`
+which by default uses Symfony's cache to store the previous login attempts.
+However, you can implement a :ref:`custom storage <rate-limiter-storage>`.
+
 Login attempts are limited on ``max_attempts`` (default: 5)
 failed requests for ``IP address + username`` and ``5 * max_attempts``
 failed requests for ``IP address``. The second limit protects against an