Use new upload artifact GitHub plugin

Author: introfog

.github/workflows/maven.yml

@@ -31,7 +31,7 @@ jobs:
 
     - name: Upload Artifact
       if: success()
-      uses: actions/upload-artifact@v2
+      uses: actions/upload-artifact@v4
       with:
         name: GitWave.zip
         path: target/GitWave.zip