[#651] Use GCS as a Bazel cache

.bazelrc

@@ -21,7 +21,7 @@ build:ci --test_env=ROOT_LOG_LEVEL=ERROR
 
 build:ci --noshow_progress
 build:ci --verbose_failures
-build:ci --disk_cache=~/.cache/bazel
-build:ci --repository_cache==~/.cache/bazel_external
+build:ci --google_credentials=/tmp/key.json
+build:ci --remote_cache=https://storage.googleapis.com/airy-ci-cache
 
 test:ci --flaky_test_attempts=2

.github/workflows/main.yml

@@ -15,14 +15,6 @@ jobs:
           java-version: '11'
           architecture: 'x64'
 
-      - name: Mount bazel cache
-        uses: actions/cache@v2
-        with:
-          path: |
-            /home/runner/.cache/bazel
-            /home/runner/.cache/bazel_external
-          key: bazel
-
       - name: Install bazelisk
         run: |
           curl -LO "https://github.com/bazelbuild/bazelisk/releases/download/v1.1.0/bazelisk-linux-amd64"
@@ -35,6 +27,7 @@ jobs:
           cat <<EOF >>.bazelrc
             common --config=ci
           EOF
+          echo ${{ secrets.GCS_SA_KEY }} > /tmp/key.json
 
       - name: Lint
         run: |