Remove feature flag `ci_support_include_rules_changes`

What does this MR do and why?

This MR removes the feature flag ci_support_include_rules_changes which was rolled out globally on 2023-09-05 9:15AM PT.

• Roll out issue: #421608 (closed)
• MR that introduced the change: !129866 (merged)

Changelog: added

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #421608 (closed)