Add test for output determinism (#86737)
These PRs are needed to get the test to pass
- [x] https://github.com/vercel/next.js/pull/86736
- [x] https://github.com/vercel/next.js/pull/86727
- [x] https://github.com/vercel/next.js/pull/86769
- [x] https://github.com/vercel/next.js/pull/86865
