Init GitHub Actions

.github/workflows/main.yml

@@ -0,0 +1,36 @@
+name: CI
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+  workflow_dispatch:
+
+jobs:
+  build:
+    strategy:
+      matrix:
+        include:
+          - os: ubuntu-22.04
+            java_version: 8
+          - os: ubuntu-22.04
+            java_version: 11
+          - os: ubuntu-22.04
+            java_version: 17
+          - os: macos-13
+            java_version: 11
+      fail-fast: false
+    runs-on: ${{ matrix.os }}
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-java@v4
+        with:
+          distribution: zulu
+          java-version: ${{ matrix.java_version }}
+
+      - uses: gradle/actions/setup-gradle@v4
+
+      - run: ./gradlew build --warning-mode all