Add scanner|site profiles form to the sidebar

What does this MR do and why?

This MR resolves #361669 (closed)

1. This MR adds scanner|site profile form to sidebar according to new design
2. This MR handles only creation of new profile, editing functionality is scope of another MR
3. Refetching of profiles will be adjusted in another MR
4. List of created profiles in the sidebar will be added in another MR after this MR is merged

Describe in detail what your merge request does and why.

Screenshots or screen recordings

After

new_form_in_side_drawer

These are strongly recommended to assist reviewers and reduce the time to merge your change.

How to set up and validate locally

1. Enable feature flag

   Feature.enable(:dast_ui_redesign)

2. Go to any project /root/$PROJECT_ID/
3. Go to /root/$PROJECT_ID/-/on_demand_scans/
4. Go to new scan form by clicking new scan
5. You have to have all scanners deleted, so you can see empty state
6. Click Select scanner|site profile

Numbered steps to set up and validate the change are strongly suggested.

MR acceptance checklist

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• I have evaluated the MR acceptance checklist for this MR.