Merge branch 'timeago-perf-fix' into 'master'

Fixed timeago re-rendering every element

## What does this MR do?

Fixes an issue when new notes are added timeago will be initialised for every timeago element on the page again and therefore adding more timeouts.

See merge request !7969

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

@@ -29,7 +29,7 @@
         setTimeago = true;
       }
 
-      $timeagoEls.each(function() {
+      $timeagoEls.filter(':not([data-timeago-rendered])').each(function() {
         var $el = $(this);
         $el.attr('title', gl.utils.formatDate($el.attr('datetime')));
 
@@ -39,6 +39,8 @@
             template: '<div class="tooltip local-timeago" role="tooltip"><div class="tooltip-arrow"></div><div class="tooltip-inner"></div></div>'
           });
         }
+
+        $el.attr('data-timeago-rendered', true);
         gl.utils.renderTimeago($el);
       });
     };

changelogs/unreleased/timeago-perf-fix.yml

+---
+title: Fixed timeago re-rendering every timeago
+merge_request: 
+author: