Ditch Docker for now, since pull requests don't have access to secrets.

.github/workflows/bazel_tests.yml

@@ -22,19 +22,6 @@ jobs:
           - { flags: "--config=asan -- -benchmarks:benchmark" }
 
     steps:
-      - name: Set up Cloud SDK
-        uses: google-github-actions/setup-gcloud@master
-        with:
-          project_id: ${{ secrets.GCP_PROJECT_ID }}
-          service_account_key: ${{ secrets.GCP_SA_KEY }}
-          export_default_credentials: true
-
-      - name: Use gcloud CLI
-        run: gcloud info
-      - name: Configure Docker
-        run: gcloud auth configure-docker
-      - name: Pull Docker Image
-        run: docker pull gcr.io/protobuf-build/bazel/linux:4.0.0-b87ca72acbc262f41506b004ac9ea0657c91b546
       - uses: actions/checkout@v2
       - name: Run tests
-        run: cd ${{ github.workspace }} && docker run -v$PWD:/workspace gcr.io/protobuf-build/bazel/linux:4.0.0-b87ca72acbc262f41506b004ac9ea0657c91b546 test ... ${{ matrix.flags }}
+        run: cd ${{ github.workspace }} && bazel test ... ${{ matrix.flags }}