Add GH Actions for PRs

* Initial `pr-build-workflow.yml`

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

@@ -0,0 +1,26 @@
+name: Pull Request build
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v2
+    - name: Set up JDK 11
+      uses: actions/setup-java@v1
+      with:
+        java-version: 11
+        
+    - name: Run Gradle
+      uses: burrunan/gradle-cache-action@v1
+      env:
+        GRADLE_ENTERPRISE_URL: https://ge.spring.io/
+      with:
+        arguments: check