minor #7598 Update load_balancer_reverse_proxy.rst (atailouloute)

This PR was merged into the 2.7 branch.

Discussion
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Update load_balancer_reverse_proxy.rst

Fix XML tag

Commits
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b467ac2 Update load_balancer_reverse_proxy.rst

Author: xabbuh

request/load_balancer_reverse_proxy.rst

@@ -47,7 +47,7 @@ and which reverse proxy IP addresses will be doing this type of thing:
 
             <framework:config trusted-proxies="192.0.0.1, 10.0.0.0/8">
                 <!-- ... -->
-            </framework>
+            </framework:config>
         </container>
 
     .. code-block:: php