Add sort runners on admin runners

Open username-removed-100770 requested to merge tnir/gitlab-ce:38720-sort-admin-runners into master

What does this MR do?

Add sort runners by last contacted on admin runners.

Are there points in the code the reviewer needs to double check?

No.

Why was this MR needed?

Admins want to clean up inactive ones from dozens of the registered runners. For that, sort runners by 'Last contacted' on admin runners would be helpful.

(from #38720)

Screenshots (if relevant)

sort-contacted-on-admin-runners

Does this MR meet the acceptance criteria?

What are the relevant issue numbers?

Closes #38720

Edited by username-removed-100770