minor #8568 Update security.rst (senenh, weaverryan)

This PR was merged into the 3.3 branch.

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Update security.rst

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e003213 more underlining!
701c95e Update security.rst

Author: weaverryan

security.rst

@@ -990,8 +990,8 @@ To accomplish this you have 2 options:
 In both cases, you'll still deny access using methods similar to what was
 shown above.
 
-Retrieving the User Object
---------------------------
+3) Retrieving the User Object
+-----------------------------
 
 After authentication, the ``User`` object of the current user can be accessed
 via the ``security.token_storage`` service. From inside a controller, this will