Add runner executor to runner details page

What does this MR do and why?

Adds runner executor to runner details page

Changelog: added

• Fix for Show the type of executor each shared Runner is... (#14335 - closed)
• Partial fix for Add more details to runner read-only view (#352885 - closed)

Depends on !85683 (merged), which should be in workflowproduction before merging this one.

Screenshots or screen recordings

How to set up and validate locally

1. With at least one runner registered
2. Visit admin -> runners -> runner (e.g. http://gdk.test:3000/admin/runners/77)
3. Confirm the executor is shown

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.