Update upload-artifact action to version 4

Author: rubensworks

.github/workflows/ci.yml

@@ -81,7 +81,7 @@ jobs:
           node-version: 16.x
       - run: npm ci --ignore-scripts
       - run: npm run docs
-      - uses: actions/upload-artifact@v2
+      - uses: actions/upload-artifact@v4
         with:
           name: docs
           path: |