Split tests in a separate step on GitHub Actions

Signed-off-by: Lars Grefer <eclipse@larsgrefer.de>

.github/workflows/maven.yml

@@ -11,19 +11,27 @@ on:
 
 jobs:
   build:
-
     runs-on: ubuntu-latest
     strategy:
       fail-fast: false
       matrix:
         java: [ 8, 11, 14 ]
     steps:
-    - uses: actions/checkout@v2
-    - name: Set up JDK ${{ matrix.java }}
-      uses: actions/setup-java@v1
-      with:
-        java-version: ${{ matrix.java }}
-    - run: java -version
-    - run: ./mvnw --version
-    - name: Build with Maven
-      run: ./mvnw -Daspectj.tests.verbose=false -B package --file pom.xml
+      - uses: actions/checkout@v2
+
+      - name: Set up JDK ${{ matrix.java }}
+        uses: actions/setup-java@v1
+        with:
+          java-version: ${{ matrix.java }}
+
+      - name: Print tool versions
+        run: |
+          java -version
+          ./mvnw -B --version
+          ant -version
+
+      - name: Compile code
+        run: ./mvnw -B -DskipTests package --file pom.xml
+
+      - name: Run Tests
+        run: ./mvnw -B -Daspectj.tests.verbose=false verify --file pom.xml