Add job setup accordion in job assistant drawer

What does this MR do and why?

!107828 (merged) is merged, now we have an empty job assistant.

This MR is part of !105538 (closed), and continue to add a job setup accordion in the drawer.

Screenshots or screen recordings

QQ20230205-235935-HD

How to set up and validate locally

1. Enable the feature flag

   Feature.enable(:ci_job_assistant_drawer)

2. Visit any CI editor pages such as http://127.0.0.1:3000/root/demo/-/ci/editor?branch_name=master

3. Click the job assistant button.

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.

/cc @daveliu