Add runner registration page

What does this MR do and why?

As part of the new registration workflow, this change adds a new page where users can find all the required information to register their runner.

In this change, page is empty while this feature is built.

Screenshots or screen recordings

Sample URL: http://gdk.test:3000/admin/runners/333/register

This page will be implemented to hold this step of the workflow:

How to set up and validate locally

Unfortunately, as we are still building our functionality under create_runner_workflow we won't have a way to verify this page directly. That will happen after both !111051 (merged) and !110593 (merged) integrate to create new runners that can be registered this way.

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 #383139 (closed)