Add github action for running unit tests on push

UserManagementAPI/.github/workflows/maven.yml

@@ -0,0 +1,25 @@
+name: Run unit tests
+
+on:
+  push:
+    branches: [ "main" ]
+
+jobs:
+  build-test-package:
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Checkout repository
+      uses: actions/checkout@v3
+
+    - name: Set up JDK 21
+      uses: actions/setup-java@v3
+      with:
+        java-version: '21'
+        cache: 'maven'
+
+    - name: Build with Maven
+      run: mvn -B package --file pom.xml
+
+    - name: Run unit tests
+      run: java -jar target/UserManagementAPI-0.0.1-SNAPSHOT.jar --runTests