Add GitHub Actions workflow for CI

.github/workflows/ci-pipeline.yml

@@ -0,0 +1,28 @@
+name: CI Pipeline for Spring Petclinic
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+
+jobs:
+  build:
+    runs-on: self-hosted
+    steps:
+      # Checkout code
+      - name: Checkout code
+        uses: actions/checkout@v3
+
+      # Set up JDK
+      - name: Set up JDK 17
+        uses: actions/setup-java@v3
+        with:
+          java-version: '17'
+          distribution: 'temurin'
+
+      # Build with Maven
+      - name: Build and test with Maven
+        run: mvn clean install