Use GitHub Action with Java 8

Author: stefanbirkner

.github/workflows/ci.yml

@@ -4,11 +4,13 @@ on: [push, pull_request]
 
 jobs:
   build:
-
-    runs-on: ubuntu-18.04
-
+    runs-on: ubuntu-slim
     steps:
-    - name: Checkout
-      uses: actions/checkout@v2
+    - uses: actions/checkout@v6
+    - uses: actions/setup-java@v5
+      with:
+        java-version: '8'
+        distribution: 'temurin'
+        cache: maven
     - name: Build and Test
-      run: scripts/test.sh
+      run: ./mvnw verify -Dgpg.skip