Switched Milestone and Release to many-to-many relationships
What does this MR do?
Setting up a many-to-many relationship at the Rails level between
Original CE merge request: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/32656
Does this MR meet the acceptance criteria?
- Changelog entry for user-facing changes, or community contribution. Check the link for other scenarios.
- Documentation created/updated or follow-up review issue created
- Code review guidelines
- Merge request performance guidelines
- Style guides
- Database guides
Performance and Testing
- Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.