Update google-github-actions/auth action to v2.1.6

Author: renovate[bot]

.github/workflows/integration_test.yml

@@ -39,7 +39,7 @@ jobs:
           flutter build apk --config-only
           patrol build android --verbose --target integration_test/auto_resize_test.dart
 
-      - uses: google-github-actions/auth@62cf5bd3e4211a0a0b51f2c6d6a37129d828611d # v2.1.5
+      - uses: google-github-actions/auth@8254fb75a33b976a221574d287e93919e6a36f70 # v2.1.6
         with:
           credentials_json: ${{ secrets.FIREBASE_TEST_LAB_CREDENTIALS_JSON }}
       - uses: google-github-actions/setup-gcloud@f0990588f1e5b5af6827153b93673613abdc6ec7 # v2.1.1
@@ -89,7 +89,7 @@ jobs:
           cd demo_app/ios
           fastlane patrol_build
 
-      - uses: google-github-actions/auth@62cf5bd3e4211a0a0b51f2c6d6a37129d828611d # v2.1.5
+      - uses: google-github-actions/auth@8254fb75a33b976a221574d287e93919e6a36f70 # v2.1.6
         with:
           credentials_json: ${{ secrets.FIREBASE_TEST_LAB_CREDENTIALS_JSON }}
       - uses: google-github-actions/setup-gcloud@f0990588f1e5b5af6827153b93673613abdc6ec7 # v2.1.1