Bump google-github-actions/auth from 0.7.2 to 0.7.3 (#832)

Bumps [google-github-actions/auth](https://github.com/google-github-actions/auth) from 0.7.2 to 0.7.3.
- [Release notes](https://github.com/google-github-actions/auth/releases)
- [Changelog](https://github.com/google-github-actions/auth/blob/main/CHANGELOG.md)
- [Commits](google-github-actions/auth@dafc924...81012c2)

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

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/build.yml

@@ -52,7 +52,7 @@ jobs:
           version: v0.11.2
 
       - name: Set up Cloud SDK
-        uses: google-github-actions/auth@dafc92490a98acbdec38e6eb649f05d55e632447 # v0.7.1
+        uses: google-github-actions/auth@81012c2689e66f7f020ed6d8ab43596a0f8b503a # v0.7.1
         with:
           workload_identity_provider: 'projects/498091336538/locations/global/workloadIdentityPools/githubactions/providers/sigstore-rekor'
           service_account: 'github-actions-rekor@projectsigstore.iam.gserviceaccount.com'