Add Github Actions to test Bazel builds. (#5043)

* Add github action to build/test code using Bazel.

* Add a cache for Bazel github actions.

.github/workflows/bazel.yml

@@ -0,0 +1,26 @@
+name: Build and Test with Bazel
+
+on: [push, pull_request]
+
+jobs:
+  build:
+    timeout-minutes: 120
+    strategy:
+      matrix:
+        os: [ubuntu-latest, macos-latest, windows-latest]
+
+    runs-on: ${{matrix.os}}
+
+    steps:
+      - uses: actions/checkout@v3
+      - name: Download dependencies
+        run: python3 utils/git-sync-deps
+      - name: Mount Bazel cache
+        uses: actions/cache@v3
+        with:
+          path: ~/.bazel/cache
+          key: bazel-cache-${{ runner.os }}
+      - name: Build All
+        run: bazel --output_user_root=~/.bazel/cache build //...
+      - name: Test All
+        run: bazel --output_user_root=~/.bazel/cache test //...

.github/workflows/wasm.yml

@@ -1,6 +1,6 @@
 name: Wasm Build
 
-on: [ push, pull_request ]
+on: [push, pull_request]
 
 jobs:
   build: