Bump polars from 0.20.30 to 0.20.31 (#93)

Bumps [polars](https://github.com/pola-rs/polars) from 0.20.30 to 0.20.31.
- [Release notes](https://github.com/pola-rs/polars/releases)
- [Commits](pola-rs/polars@py-0.20.30...py-0.20.31)

---
updated-dependencies:
- dependency-name: polars
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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