Use single space after commas in index-list.html

This is unnecessary since in HTML whitespace is collapsed
when rendering the page.

Note:
The replacement command that's removed in this commit
was first introduced in commit 6c29e87,
when the `helpers/generate-index-list-html.js` file
was still called `lib/create-catalog.js`.

helpers/generate-index-list-html.js

@@ -62,8 +62,8 @@ html += _.map(emojisList, (e, i) => {
  <td>${e.group}</td>
  <td>${e.subgroups}</td>
  <td>${e.annotation}</td>
- <td>${e.tags.replace(/,/g, ', ')}</td>
- <td>${e.openmoji_tags.replace(/,/g, ', ')}</td>
+ <td>${e.tags}</td>
+ <td>${e.openmoji_tags}</td>
  <td>${e.openmoji_author}</td>
  <td><a download href="src/${e.group +'/'+ e.subgroups +'/'+ e.hexcode +'.svg'}">⬇</a></td>
  </tr>`;