Auto merge of #15029 - aneeshusa:check-whole-constellation-for-panics, r=asajeffrey

Check all constellation files for panics

Teaches the `etc/ci/check_no_panic.sh` script to handle directories,
so it can check all constellation files for panics.

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r? @asajeffrey
There are currently 4 `unwrap()`s in `components/constellation/timer_scheduler.rs`; I'm not sure how you want to handle those.

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- [ ] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #14976 (github issue number if applicable).

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- [x] These changes do not require tests because it adds more testing coverage

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