Bump google-auth from 2.25.2 to 2.26.0

Bumps [google-auth](https://github.com/googleapis/google-auth-library-python) from 2.25.2 to 2.26.0.
- [Release notes](https://github.com/googleapis/google-auth-library-python/releases)
- [Changelog](https://github.com/googleapis/google-auth-library-python/blob/main/CHANGELOG.md)
- [Commits](googleapis/google-auth-library-python@v2.25.2...v2.26.0)

---
updated-dependencies:
- dependency-name: google-auth
  dependency-type: indirect
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>