minor #9924 Link to proxy configuration docs from the routing scheme page (colinodell, javiereguiluz)

This PR was submitted for the 2.7 branch but it was merged into the 2.8 branch instead (closes #9924).

Discussion
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Link to proxy configuration docs from the routing scheme page

This should help developers avoid infinite redirect loops.

See symfony/symfony#27603

Commits
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671e13c Reword and added a note
c717e75 Link to proxy configuration docs from the routing scheme page

Author: javiereguiluz

security/force_https.rst

@@ -105,3 +105,10 @@ role:
 
 It is also possible to specify using HTTPS in the routing configuration,
 see :doc:`/routing/scheme` for more details.
+
+.. note::
+
+    Forcing HTTPS while using a reverse proxy or load balancer requires a proper
+    configuration to avoid infinite redirect loops; see :doc:`/deployment/proxies`
+    for more details.
+