Bump google-github-actions/auth from 2.1.7 to 2.1.8

Bumps [google-github-actions/auth](https://github.com/google-github-actions/auth) from 2.1.7 to 2.1.8.
- [Release notes](https://github.com/google-github-actions/auth/releases)
- [Changelog](https://github.com/google-github-actions/auth/blob/main/CHANGELOG.md)
- [Commits](https://github.com/google-github-actions/auth/compare/6fc4af4b145ae7821d527454aa9bd537d1f2dc5f...71f986410dfbc7added4569d411d040a91dc6935

)

---
updated-dependencies:
- dependency-name: google-github-actions/auth
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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