title: Unexpected comma using map()
body: <p>I've an array with a list of elements and I'm trying to append this list to an HTML element using template strings:</p>
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>var description = [
    'HTML &amp; CSS',
    'Javascript object-oriented programming',
    'Progressive Web apps (PWAs)',
    'Website Performance Optimization',
    'Webpack and Gulp workflows',
    'Fullstack React.js',
    'Web Components',
    'Responsive web design',
    'Sketch design',
    'GraphQL and Relay'
  ]
  
  $('body').append(
    `
    &lt;div class="description"&gt;
      &lt;ul&gt;
        ${description.map(
          function(work) {
            return `&lt;li&gt;${work}&lt;/li&gt;`
          }
        )}&lt;/ul&gt;
    &lt;/div&gt;
    `
  )</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"&gt;&lt;/script&gt;</code></pre>
  </div>
  </div>
  </p>
  <p>As a result I get an unexpected comma between each list element. (You can see this when you run the code snippet above.)</p>
  <p>How can I avoid this?</p>