Bump pyarrow-stubs in the dependencies group

Bumps the dependencies group with 1 update: [pyarrow-stubs](https://github.com/zen-xu/pyarrow-stubs).


Updates `pyarrow-stubs` from 20.0.0.20250825 to 20.0.0.20250928
- [Release notes](https://github.com/zen-xu/pyarrow-stubs/releases)
- [Commits](zen-xu/pyarrow-stubs@20.0.0.20250825...20.0.0.20250928)

---
updated-dependencies:
- dependency-name: pyarrow-stubs
  dependency-version: 20.0.0.20250928
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: dependencies
...

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Author: dependabot[bot]