minor #13818 Update authorization.rst (atailouloute)

This PR was merged into the 5.0 branch.

Discussion
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Update authorization.rst

The ExpressionVoter does not provide anymore the `roles` variables, `role_names` should be used

Commits
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5b032d0 Update authorization.rst

Author: javiereguiluz

components/security/authorization.rst

@@ -185,7 +185,7 @@ expressions have access to a number of
     $object = ...;
 
     $expression = new Expression(
-        '"ROLE_ADMIN" in roles or (not is_anonymous() and user.isSuperAdmin())'
+        '"ROLE_ADMIN" in role_names or (not is_anonymous() and user.isSuperAdmin())'
     )
 
     $vote = $expressionVoter->vote($token, $object, [$expression]);