title: Venn diagram not getting rendered in highcharter package
body: <p>I am trying to emulate <a href="https://jsfiddle.net/gh/get/library/pure/highcharts/highcharts/tree/master/samples/highcharts/demo/venn-diagram/" rel="nofollow noreferrer">this</a> venn diagram from highcharts API using <a href="https://cran.r-project.org/web/packages/highcharter/vignettes/replicating-highcharts-demos.html" rel="nofollow noreferrer">this</a> as a guide.</p>
  
  <p>Following is the code I am writing in R:</p>
  
  <pre><code>library(highcharter)
  
  highchart() %&gt;% 
    hc_series(
      list(
        type = "venn",
        name = "Venn Diagram",
        data = list(
          list(sets = c("Good"), value = 2),
          list(sets = c("Fast"), value = 2),
          list(sets = c("Good", "Fast"), value = 1)
        )
      )
    )
  </code></pre>
  
  <p>When I run this code, nothing gets rendered.</p>
  
  <p>What am I missing in this code?</p>