Fix Mermid diagrams in vignettes (#96)

* Use pre-release Quarto in pkgdown workflow

* Upload built site as artifact in pkgdown workflow

.github/workflows/pkgdown.yaml

@@ -39,6 +39,7 @@ jobs:
         with:
           extra-packages: any::pkgdown, local::.
           needs: website
+          quarto-version: pre-release
 
       - name: Install lamindb
         run: |
@@ -56,6 +57,12 @@ jobs:
         run: pkgdown::build_site_github_pages(new_process = FALSE, install = FALSE)
         shell: Rscript {0}
 
+      - name: Create built site artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: pkgdown-site
+          path: docs
+
       - name: Deploy to GitHub pages 🚀
         if: github.event_name != 'pull_request'
         uses: JamesIves/github-pages-deploy-action@v4