Resolve "Implement Notebook Diff usage Metrics"
Adds usage data events for note creation on Ipynb diffs and MRs
How to reproduce
This doesn't add any visual changes, but we can test for degradation:
- Open a commit with a Jupyter Notebook (eg http:///gitlab-org/gitlab-test/-/commit/5d6ed1503801ca9dc28e95eeb85a7cf863527aee)
- Enable the feature flag
Feature.enable(:ipynbdiff_notes_tracker)
- Add a comment
- Verify that the comment was added correctly
Related to #353407 (closed)