added github action

.github/workflows/build.yml

@@ -0,0 +1,23 @@
+# .github/workflows/gradle-build-pr.yml
+name: Run Gradle on pushs
+on:
+  push:
+    branches:
+      - '*'
+  pull_request:
+    branches:
+      - '*'
+jobs:
+  gradle:
+    strategy:
+      matrix:
+        os: [ubuntu-latest, macos-latest, windows-latest]
+    runs-on: ${{ matrix.os }}
+    steps:
+      - uses: actions/checkout@v1
+      - uses: actions/setup-java@v1
+        with:
+          java-version: 11
+      - uses: eskatos/gradle-command-action@v1
+        with:
+          arguments: build