fix formatting error preventing page from being rendered

Author: michaelbabyn

_posts/plotly_js/chart-events/events/2018-08-06-order6_legendclick_event.html

@@ -9,7 +9,7 @@
 markdown_content: |
   `plotly_legendclick` and `plotly_legenddoubleclick` allow customization of the plotly legend. The default behaviour of `plotly_legendclick` is to hide a trace and the default behavior of `plotly_legenddoubleclick` is to select one trace and hide all the others. 
   We can add to the default behaviour by creating a new `plotly_legendclick` event with a function of our choice. We can also disable the default behaviour by creating a function that returns `false`. In the example below, we do both in order to create a `plotly_legendclick` event which changes the marker color back to black instead of erasing the trace.
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 var myPlot = document.getElementById('myDiv'),
     x = [1, 2, 3, 4, 5, 6],