chore(deps): bump google-auth-httplib2 in /classroom/quickstart

Bumps [google-auth-httplib2](https://github.com/GoogleCloudPlatform/google-auth-library-python-httplib2) from 0.0.3 to 0.3.0.
- [Release notes](https://github.com/GoogleCloudPlatform/google-auth-library-python-httplib2/releases)
- [Changelog](https://github.com/googleapis/google-auth-library-python-httplib2/blob/main/CHANGELOG.md)
- [Commits](https://github.com/GoogleCloudPlatform/google-auth-library-python-httplib2/commits/v0.3.0)

---
updated-dependencies:
- dependency-name: google-auth-httplib2
  dependency-version: 0.3.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Author: dependabot[bot]

classroom/quickstart/requirements.txt

@@ -1,3 +1,3 @@
 google-api-python-client==1.7.9
-google-auth-httplib2==0.0.3
+google-auth-httplib2==0.3.0
 google-auth-oauthlib==0.4.0