minor #15546 Fix wrong option flag name (antograssiot)

This PR was merged into the 5.3 branch.

Discussion
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Fix wrong option flag name

It seems that the documented option doesn't exists in the new `debug:firewall` command

Commits
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3a1bbc8 Fix wrong option flag name

Author: javiereguiluz

reference/configuration/security.rst

@@ -500,7 +500,7 @@ the ``debug:firewall`` command:
 
     # displays the details of a specific firewall, including detailed information
     # about the event listeners for the firewall
-    $ php bin/console debug:firewall main --include-listeners
+    $ php bin/console debug:firewall main --events
 
 .. versionadded:: 5.3