minor #13836 Update authorization.rst (zairigimad)

This PR was submitted for the 5.0 branch but it was merged into the 3.4 branch instead.

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Update authorization.rst

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7835687 Update authorization.rst

Author: javiereguiluz

components/security/authorization.rst

@@ -47,7 +47,7 @@ recognizes several strategies:
     grant access if there are more voters granting access than there are denying;
 
 ``unanimous``
-    only grant access if none of the voters has denied access;
+    only grant access if none of the voters has denied access. If all voters abstained from voting, the decision is based on the ``allow_if_all_abstain`` config option (which defaults to ``false``);
 
 Usage of the available options in detail::