Bump google-auth from 2.23.4 to 2.28.0

Bumps [google-auth](https://github.com/googleapis/google-auth-library-python) from 2.23.4 to 2.28.0.
- [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@v2.23.4...v2.28.0)

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

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

Pipfile

@@ -31,7 +31,7 @@ langchain = "==0.0.352"
 langchain-experimental = "==0.0.40"
 anyio = "<4.0.0" # Do not update: anyio<4.0 is REQUIRED by langchain
 google-api-core = "==2.11.1"
-google-auth = "==2.23.4"
+google-auth = "==2.28.0"
 google-cloud-core = "==2.3.3"
 google-cloud-speech = "==2.21.0"
 google-cloud-texttospeech = "==2.14.2"