Update actions for Node 20 (#40)

Move gradle wrapper validation inline

Author: sciencewhiz

.github/workflows/gradle-wrapper-validation.yml

@@ -6,25 +6,28 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v4
       with:
         fetch-depth: 0
-    - uses: actions/setup-java@v1
+    - uses: gradle/actions/wrapper-validation@v3
+    - uses: actions/setup-java@v4
       with:
         java-version: 11
+        distribution: 'zulu'
     - name: Build
       run: ./gradlew build -PbuildServer
 
   publish:
     needs: build
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
         with:
           fetch-depth: 0
-      - uses: actions/setup-java@v1
+      - uses: actions/setup-java@v4
         with:
           java-version: 11
+          distribution: 'zulu'
       - name: Publish
         if: ${{ !startsWith(github.ref, 'refs/tags/v') }}
         run: ./gradlew publishToMavenLocal -PbuildServer