ci(fix): checkout before doing path filtering (#9920)
### Description
We're seeing sporadic failures on the `dorny/paths-filter` part, and[
the recommended
recourse](https://github.com/dorny/paths-filter/issues/24#issuecomment-841818275)
from the workflow author is to add a checkout.
Failures:
-
https://github.com/vercel/turborepo/actions/runs/13208878667/job/36878355246
-
https://github.com/vercel/turborepo/actions/runs/13205111177/job/36866322671
However, it's notable that it looks like GHA just...does this sometimes?
- https://github.com/actions/checkout/issues/417
- https://github.com/actions/runner-images/issues/9632
- https://github.com/actions/runner-images/issues/9882
### Testing Instructions
CI
