Added a GitHub action for checking the build process (using maven clean test) on each push/pull request to the "main" branch.

Author: roimenashe

.github/build.yml

@@ -0,0 +1,31 @@
+name: Build project
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      # Checkout repo using https://github.com/marketplace/actions/checkout
+      - name: Checkout
+        uses: actions/checkout@v2
+
+      - name: Set up JDK 1.8
+        uses: actions/setup-java@v1
+        with:
+          java-version: 1.8
+
+      # See: https://github.com/actions/cache/blob/master/examples.md#java---maven
+      - name: Maven cache and restore deps
+        uses: actions/cache@v1
+        with:
+          path: ~/.m2/repository
+          key: ${{ runner.os }}-maven-${{ hashFiles('**/pom.xml') }}
+          restore-keys: |
+            ${{ runner.os }}-maven-
+      - name: Build with Maven
+        run: mvn clean test -B -U