Add Mavan build and test to CI pipeline

.github/workflows/build.yml

@@ -0,0 +1,21 @@
+
+name: Maven build and test
+
+on:
+  push
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+      - name: Set up JDK 21
+        uses: actions/setup-java@v4
+        with:
+          java-version: '21'
+          distribution: 'adopt'
+          cache: maven
+      - name: Build with Maven
+        run: mvn clean install