fix github workflow

Author: LabyStudio

.github/workflows/gradle.yml

@@ -22,7 +22,7 @@ jobs:
     - name: Build with Gradle
       run: ./gradlew build
     - name: Upload jar
-      uses: actions/upload-artifact@v1
+      uses: actions/upload-artifact@v4
       with:
         name: Plugin jar file
         path: build/libs/singlehotswap.jar