Only fetchIssuable on changes to subscribed commands.

app/assets/javascripts/time_tracking_display.js.es6

@@ -45,7 +45,10 @@
           },
           listenForSlashCommands() {
             $(document).on('ajax:success', '.gfm-form', (e, data) => {
-              if (data.commands_changes !== null) {
+              const subscribedCommands = ['spend_time', 'time_estimate'];
+              const changedCommands = data.commands_changes;
+
+              if (changedCommands && _.intersection(subscribedCommands, changedCommands).length) {
                 this.fetchIssuable();
               }
             });