Add a total number of jobs run by a runner

What does this MR do and why?

This change adds back the total number of jobs that a runner has run in the admin view.

See: #347250 (closed)

See related removal MR: !73472 (merged)

Screenshots or screen recordings

How to set up and validate locally

1. Visit http://gdk.test:3000/admin/runners
2. Confirm the job count

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 #347250 (closed)