Bump google-cloud-kms from 3.2.0 to 3.2.1 in /docker/google-kms

Bumps [google-cloud-kms](https://github.com/googleapis/google-cloud-python) from 3.2.0 to 3.2.1.
- [Release notes](https://github.com/googleapis/google-cloud-python/releases)
- [Changelog](https://github.com/googleapis/google-cloud-python/blob/main/packages/google-cloud-documentai/CHANGELOG.md)
- [Commits](googleapis/google-cloud-python@google-cloud-kms-v3.2.0...google-cloud-kms-v3.2.1)

---
updated-dependencies:
- dependency-name: google-cloud-kms
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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