Update version of actions/upload-artifact

Author: donmendelson

.github/workflows/maven.yml

@@ -23,7 +23,7 @@ jobs:
     - name: Build with Maven
       run: mvn -B package --file pom.xml
     - name: Upload package
-      uses: actions/upload-artifact@v2
+      uses: actions/upload-artifact@v4
       with:
         name: Package
         path: target/*.jar