Bump actions/upload-pages-artifact from 3 to 4 (#58)

Author: dependabot[bot]

.github/workflows/publish_docs.yaml

@@ -45,7 +45,7 @@ jobs:
       - run: docfx docs/docfx.json
 
       - name: Upload artifact
-        uses: actions/upload-pages-artifact@v3
+        uses: actions/upload-pages-artifact@v4
         with:
           # Upload entire repository
           path: "docs/_site"