poetry: bump boto3-stubs from 1.34.67 to 1.40.50

Bumps [boto3-stubs](https://github.com/youtype/mypy_boto3_builder) from 1.34.67 to 1.40.50.
- [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-version: 1.40.50
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]