fix width typo

Author: LiamConnors

_posts/plotly_js/scientific/heatmap/2015-08-12-heatmap-with-unequal-block-sizes.html

@@ -103,7 +103,7 @@
   xaxis: axisTemplate,
   yaxis: axisTemplate,
   showlegend: false,
-  with: 700,
+  width: 700,
   height: 700,
   autosize: false
 };