Remove reference to unused js-timeago-render class

Apparently the `.js-timeago-render` class serves no real purpose. All
functions that used it, directly pass a list of elements. Only one Vue
component had an (unnecessary) reference to the class. No styles are
applied.

app/assets/javascripts/diffs/components/compare_versions_dropdown.vue

@@ -141,7 +141,7 @@ export default {
                   <time-ago
                     v-if="version.created_at"
                     :time="version.created_at"
-                    class="js-timeago js-timeago-render"
+                    class="js-timeago"
                   />
                 </small>
               </div>

app/assets/javascripts/lib/utils/datetime_utility.js

@@ -133,44 +133,28 @@ export const getTimeago = () => {
 };
 
 /**
- * For the given element, renders a timeago instance.
- * @param {jQuery} $els
+ * For the given elements, sets a tooltip with a formatted date.
+ * @param {JQuery} $timeagoEls
+ * @param {Boolean} setTimeago
  */
-export const renderTimeago = $els => {
-  const timeagoEls = $els || document.querySelectorAll('.js-timeago-render');
+export const localTimeAgo = ($timeagoEls, setTimeago = true) => {
+  getTimeago().render($timeagoEls, timeagoLanguageCode);
 
-  // timeago.js sets timeouts internally for each timeago value to be updated in real time
-  getTimeago().render(timeagoEls, timeagoLanguageCode);
-};
+  if (!setTimeago) {
+    return;
+  }
 
-/**
- * For the given elements, will add timeago tooltips
- */
-export const addTimeAgoTooltip = () => {
-  const timeagoEls = document.querySelectorAll('.js-timeago-render');
-  timeagoEls.forEach(element => {
-    $(element).tooltip({
+  function addTimeAgoTooltip() {
+    $timeagoEls.each((i, el) => {
+      // Recreate with custom template
+      $(el).tooltip({
         template:
           '<div class="tooltip local-timeago" role="tooltip"><div class="arrow"></div><div class="tooltip-inner"></div></div>',
       });
     });
-};
-
-/**
- * For the given elements, sets a tooltip with a formatted date.
- * @param {jQuery}
- * @param {Boolean} setTimeago
- */
-export const localTimeAgo = ($timeagoEls, setTimeago = true) => {
-  $timeagoEls.each((i, el) => {
-    el.classList.add('js-timeago-render');
-  });
-
-  renderTimeago($timeagoEls);
+  }
 
-  if (setTimeago) {
   requestIdleCallback(addTimeAgoTooltip);
-  }
 };
 
 /**