minor symfony#6541 Trusted proxies were removed when URL signing took over (rawkode)

This PR was submitted for the master branch but it was merged into the 2.3 branch instead (closes symfony#6541).

Discussion
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Trusted proxies were removed when URL signing took over

Since: symfony/http-kernel@fa8f4f8

Commits
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853825b Removing incorrect reference that the FragmentListener only listens to ``trusted_proxies``

Author: wouterj

book/http_cache.rst

@@ -1207,11 +1207,6 @@ One great advantage of the ESI renderer is that you can make your application
 as dynamic as needed and at the same time, hit the application as little as
 possible.
 
-.. tip::
-
-    The listener only responds to local IP addresses or
-    :doc:`trusted proxies </cookbook/request/load_balancer_reverse_proxy>`.
-
 .. note::
 
     Once you start using ESI, remember to always use the ``s-maxage``

cookbook/request/load_balancer_reverse_proxy.rst

@@ -88,7 +88,7 @@ In this case, you'll need to - *very carefully* - trust *all* proxies.
        $response = $kernel->handle($request);
        // ...
 
-#. Ensure that the trusted_proxies setting in your ``app/config/config.yml`` 
+#. Ensure that the trusted_proxies setting in your ``app/config/config.yml``
    is not set or it will overwrite the ``setTrustedProxies`` call above.
 
 That's it! It's critical that you prevent traffic from all non-trusted sources.