Fix merge checks group name fetching issue

What does this MR do and why?

• Introduced in !102863 (merged)
• Connect #393316 (closed)

Fix the issue when rule enforced by the parent group on a group, the tooltip text says it was enforced by itself.

/cc @luzhiyuan.deer @mtan-gitlab

Describe in detail what your merge request does and why.

Screenshots or screen recordings

Screenshots are required for UI changes, and strongly recommended for all other merge requests.

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

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.