Update gh_pages_doc.yml

.github/workflows/gh_pages_doc.yml

@@ -32,9 +32,15 @@ jobs:
       - run: |
           sphinx-multiversion docs/source _build/html
 
-      # Conditional deployment step
+      - name: Create 'stable' version
+        if: github.event_name == 'push' && (github.ref == 'refs/heads/master' || startsWith(github.ref, 'refs/tags/'))
+        run: |
+          latest_tag=$(git tag --sort=-v:refname | head -n 1)
+          echo "Latest tag is: $latest_tag"
+          cp -r _build/html/$latest_tag _build/html/stable
+
       - name: Deploy to GitHub Pages
-        if: github.event_name == 'push' # Only run on push to main branch, not on PRs
+        if: github.event_name == 'push' && (github.ref == 'refs/heads/master' || startsWith(github.ref, 'refs/tags/'))
         uses: peaceiris/actions-gh-pages@v3
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}