Track MR approvals from the Review Drawer

What does this MR do and why?

Adds a tracking event - mr_approved_from_review_drawer - to the Review panel.

Screenshots or screen recordings

N/A, telemetry only.

How to set up and validate locally

1. Have an MR in a project
2. If you created the MR, ensure that the merge request settings for your project allow approval by the MR author
3. Visit the MR and create a draft comment
4. Click the "Your review (#)" button in the tabs header
5. Select the "Approve" radio button
6. Click "Submit review"
7. Note the request sent to /api/v4/usage_data/track_event with the event mr_approved_from_review_drawer
   • Note the correct values provided to the event: reviewer (whether you are an assigned reviewer or not), comments (how many draft comments there were in this review), and summary (whether you entered a comment).
   • Repeat as necessary to test other values (for example, when you approve but have a different reviewer status).

MR acceptance checklist

Evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.