adding build pipeline job

.github/workflows/build.yaml

@@ -0,0 +1,38 @@
+name: Java CI Build
+
+on:
+  push:
+    branches:
+      - githubactions-deploy
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Checkout Repository
+      uses: actions/checkout@v2
+
+    - name: Set up JDK 8
+      uses: actions/setup-java@v2
+      with:
+        java-version: '8'
+        distribution: 'adopt'
+
+    - name: Cache Maven Packages
+      uses: actions/cache@v2
+      with:
+        path: ~/.m2
+        key: ${{ runner.os }}-m2-${{ hashFiles('**/pom.xml') }}
+        restore-keys: ${{ runner.os }}-m2
+
+    - name: Maven Build
+      run: mvn -B package --file pom.xml
+
+    - name: Build and Push Docker Image
+      uses: docker/build-push-action@v2
+      with:
+        context: .
+        file: build/maven/Dockerfile
+        push: true
+        tags: user/repo:tag