Bump boto3-stubs from 1.26.126 to 1.28.15.post1

Bumps [boto3-stubs](https://github.com/youtype/mypy_boto3_builder) from 1.26.126 to 1.28.15.post1.
- [Release notes](https://github.com/youtype/mypy_boto3_builder/releases)
- [Commits](https://github.com/youtype/mypy_boto3_builder/commits)

---
updated-dependencies:
- dependency-name: boto3-stubs
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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