chore(deps): update actions/upload-pages-artifact action to v4 (#20)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/deploy.yml

@@ -42,7 +42,7 @@ jobs:
     
       # Upload the generated site as an artifact for the deploy job
       - name: 📤 Upload artifact
-        uses: actions/upload-pages-artifact@v3
+        uses: actions/upload-pages-artifact@v4
         with:
           path: _site  # Directory containing the built site