minor #21548 [Security] Document role hierarchy dump debug command (94noni)

This PR was merged into the 7.4 branch.

Discussion
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[Security] Document role hierarchy dump debug command

close #21350
cc `@damienfern`

fyi I got inspiration on text on the workflow dump, but didnt created a new page

Commits
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a6d9c2e Document role hierarchy dump debug command

Author: javiereguiluz

security.rst

@@ -2265,6 +2265,18 @@ Users with ``ROLE_SUPER_ADMIN``, will automatically have ``ROLE_ADMIN``,
     :doc:`security voter </security/voters>` that looks for the user roles
     in the database.
 
+.. versionadded:: 7.4
+
+    To help you debug your roles hierarchy, you can generate a visual representation
+    of them as SVG or PNG images. First, install the free and open source
+    `Mermaid CLI`_, providing the ``mmdc`` command, then executes::
+
+    .. code-block:: terminal
+        
+        $ php bin/console debug:security:role-hierarchy | mmdc -o roles.svg
+
+    You can open the file `roles.svg` to see the graph.
+
 .. _security-role-authorization:
 
 Add Code to Deny Access
@@ -3132,3 +3144,4 @@ Authorization (Denying Access)
 .. _`Login CSRF attacks`: https://en.wikipedia.org/wiki/Cross-site_request_forgery#Forging_login_requests
 .. _`PHP date relative formats`: https://www.php.net/manual/en/datetime.formats.php#datetime.formats.relative
 .. _`Oauth2-client`: https://github.com/thephpleague/oauth2-client
+.. _`Mermaid CLI`: https://github.com/mermaid-js/mermaid-cli