Add rules to not supported list for persisted variables

doc/ci/variables/where_variables_can_be_used.md

@@ -174,7 +174,7 @@ They are:
   - Script execution shell.
 - Not supported:
   - For definitions where the ["Expansion place"](#gitlab-ciyml-file) is GitLab.
-  - In the `only` and `except` [variables expressions](../jobs/job_control.md#cicd-variable-expressions).
+  - In the `only`, `except`, and `rules` [variables expressions](../jobs/job_control.md#cicd-variable-expressions).
 
 Some of the persisted variables contain tokens and cannot be used by some definitions
 due to security reasons.