Add basic CI action

Author: fmeum

.github/workflows/run-all-tests.yml

@@ -0,0 +1,34 @@
+name: Build all targets and run all tests
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+  workflow_dispatch:
+
+jobs:
+     
+  build_and_test:
+    runs-on: ubuntu-latest
+    
+    steps:
+      - uses: actions/checkout@v2
+      
+      - name: Set up JDK
+        uses: actions/setup-java@v1
+        with:
+          java-version: 11
+      
+      - name: Mount bazel cache
+        uses: actions/cache@v2
+        with:
+          path: "/home/runner/.cache/bazel"
+          key: bazel
+
+      - name: Build
+        run: ./bazelisk-linux-amd64 build -c opt //...
+
+      - name: Test
+        run: ./bazelisk-linux-amd64 test -c opt //...