Add gitlab ui visual test
What does this MR do?
Adds a new job to the pipeline to test whether our MRs affect the UI of the gitlab-ui components by running the visual regression test using the application.css generated in each MR.
What are the relevant issue numbers?
Does this MR meet the acceptance criteria?
- Changelog entry added, if necessary
- Documentation created/updated
- Tests added for this feature/bug
- Tested in all supported browsers
- Conforms to the code review guidelines
- Conforms to the merge request performance guidelines
- Conforms to the style guides
- Conforms to the database guides
- Link to e2e tests MR added if this MR has Requires e2e tests label. See the Test Planning Process.
- Security reports checked/validated by reviewer