Migrate building PRs to GitHub Action

See gh-345

.github/workflows/pr-build-workflow.yml

@@ -0,0 +1,23 @@
+name: Pull Request build
+
+on:
+  pull_request:
+    branches: [ main ]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+
+      - uses: actions/checkout@v3
+
+      - name: Set up JDK
+        uses: actions/setup-java@v3
+        with:
+          distribution: 'temurin'
+          java-version: 17
+
+      - name: Build with Maven
+        run: mvnw --batch-mode --update-snapshots verify