Make `GITALY_SERVER_VERSION` version bump approvable by maintainers

What does this MR do and why?

Currently GITALY_SERVER_VERSION can only be approved by @project_278964_bot6 which causes an issue if the Gitaly version update has an issue with Rails compatibility as seen in !96692 (closed).

This makes it impossible to fix, as only the release-bot user can approve, and non of maintainers or delivery members not allowing to merge a change like !96588 (merged).

This fixes that by allowing the version bump to be approved by maintainers and delivery members. This was the pattern used before making this change in !96696 (merged).

References

• This is problem in workflow introduced by !96696 (merged).
• This was a problem noticed as part of the !96588 (comment 1088486816), with relevant Slack discussion how to resolve it https://gitlab.slack.com/archives/CCFV016SV/p1662392784550359
• Another MR showing that if there's a Gitaly version update bug it cannot be resolved: !96692 (closed)

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.