scheduler: Add the ability to suppress `Running seed` output (#57525)

This is useful when running tests for a large number of iterations
noninteractively

Self-Review Checklist:

- [x] I've reviewed my own diff for quality, security, and reliability
- [x] Unsafe blocks (if any) have justifying comments
- [x] The content is consistent with the [UI/UX
checklist](https://github.com/zed-industries/zed/blob/main/CONTRIBUTING.md#uiux-checklist)
- [ ] Tests cover the new/changed behavior
- [x] Performance impact has been considered and is acceptable

Release Notes:

- N/A
de529b5677Cole Miller committed on 5/22/2026, 6:49:48 PM· committed by GitHubparent835cd84
1 file changedLine totals unavailable