Update README.md

Author: cldougl

_posts/plotly_js/README.md

@@ -100,7 +100,7 @@ Our javascript tutorials are written in HTML files with embeded [codepen](http:/
   - `git push origin source-design-merge`
 
 10. To proof your work follow these steps: https://github.com/plotly/documentation/blob/source/Contributing.md#rendering-the-pages-locally 
-11. Deploy with `rake deploy`
+11. Deploy with `bundle exec rake deploy`
 
 ##### At https://plot.ly/javascript
 12. Check your Tutorial!!!! This is a <b>very important</b> step.