Clean up group runner permissions

What does this MR do and why?

This is a small preparatory change before enabling group maintainers access to the groups runners list.

Clean up group runner permissions (!128975 - merged)	you are here
Allows group maintainers to see group runners list (!128607 - merged)

Screenshots or screen recordings

NA

How to set up and validate locally

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 #384179 (closed)