CI: Run pre-commit on depot machine (#17120)
## Summary
Sibling/alternate of #17108 (see
https://github.com/astral-sh/ruff/pull/17108#issuecomment-2769200896).
See if running the pre-commit CI step on Depot machines makes
WASM-compiled shellcheck faster.
## Test Plan
> How was it tested?
We're doing it live!
