Update jdk-ea build

Author: rbygrave

.github/workflows/jdk-ea.yml

@@ -20,20 +20,22 @@ jobs:
         os: [ubuntu-latest]
 
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
     - name: Set up Java
       uses: oracle-actions/setup-java@v1
       with:
         website: jdk.java.net
         release: ${{ matrix.java_version }}
     - name: Maven cache
-      uses: actions/cache@v2
+      uses: actions/cache@v4
       env:
         cache-name: maven-cache
       with:
         path:
           ~/.m2
         key: build-${{ env.cache-name }}
+    - name: Maven version
+      run: mvn --version
     - name: Build with Maven
       run: mvn clean test -Pdefault