update to actions/upload-artifact@v4

Author: jaehyeon-kim

.github/workflows/doc.yml

@@ -25,7 +25,7 @@ jobs:
         uses: ammaraskar/[email protected]
 
       - name: Upload artifacts
-        uses: actions/upload-artifact@v1
+        uses: actions/upload-artifact@v4
         with:
           name: html-docs
           path: docs/_build/html/
@@ -34,4 +34,4 @@ jobs:
         uses: peaceiris/actions-gh-pages@v3
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
-          publish_dir: docs/_build/html
+          publish_dir: docs/_build/html