Bump google-auth from 2.6.0 to 2.6.2 in /requirements (#18996)

Bumps [google-auth](https://github.com/googleapis/google-auth-library-python) from 2.6.0 to 2.6.2.
- [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](https://github.com/googleapis/google-auth-library-python/compare/v2.6.0...v2.6.2)

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

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

requirements/prod.txt

@@ -457,9 +457,9 @@ zipp==3.7.0 \
 google-cloud-bigquery==2.34.2 \
     --hash=sha256:0eb882df30a00f5a1ef3d339a23a670230800b2ab249459591a7e685aad6714f \
     --hash=sha256:bd7de9e3126ea0975d1f5b25e69c28b644c69821c229327e64b38e44fb16497e
-google-auth==2.6.0 \
-    --hash=sha256:218ca03d7744ca0c8b6697b6083334be7df49b7bf76a69d555962fd1a7657b5f \
-    --hash=sha256:ad160fc1ea8f19e331a16a14a79f3d643d813a69534ba9611d2c80dc10439dad
+google-auth==2.6.2 \
+    --hash=sha256:3ba4d63cb29c1e6d5ffcc1c0623c03cf02ede6240a072f213084749574e691ab \
+    --hash=sha256:60d449f8142c742db760f4c0be39121bc8d9be855555d784c252deaca1ced3f5
 google-api-core==2.7.1 \
     --hash=sha256:6be1fc59e2a7ba9f66808bbc22f976f81e4c3e7ab20fa0620ce42686288787d0 \
     --hash=sha256:b0fa577e512f0c8e063386b974718b8614586a798c5894ed34bedf256d9dae24