Adjust toggle behaviour for runner registration token setting at group

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What does this MR do and why?

When the toggle is enabled or disabled, the page refreshes, which causes a bad UX. This change aims to fix that by making an async axios call without page refresh.

Closes: #455063 (closed)

Changelog: changed

Screenshots or screen recordings

Before	After
before.mov	after.mov

How to set up and validate locally

1. Run GitLab .
2. Navigate to <group> -> Settings -> CI/CD .
3. Expand the Runners section.
4. Toggle the Allow members of projects and groups to create runners with runner registration tokens setting.