Fix require errors exposed by removing tooltip directive.

app/assets/javascripts/issuable_time_tracker.js.es6

-//= vue
+//= require vue
 
 (() => {
   gl.IssuableTimeTracker = Vue.component('issuable-time-tracker', {

app/assets/javascripts/time_tracking_display.js.es6

 //= require vue
-//= issuable_time_tracker
-//= smart_interval
-//= subbable_resource
+//= require issuable_time_tracker
+//= require smart_interval
+//= require subbable_resource
 
 (() => {
   /* This Vue instance represents what will become the parent instance for the

spec/javascripts/smart_interval_spec.js.es6

-
 //= require jquery
 //= require smart_interval