Remove DOMContentLoaded Events

Removing DOMContentLoaded Events from
index files since the scripts
are embedded using the defer tag.

ee/app/assets/javascripts/pages/groups/show/index.js

@@ -5,12 +5,9 @@ import initVueAlerts from '~/vue_alerts';
 import initInviteMembersTrigger from '~/invite_members/init_invite_members_trigger';
 import initInviteMembersModal from '~/invite_members/init_invite_members_modal';
 
-document.addEventListener('DOMContentLoaded', () => {
-  leaveByUrl('group');
-
-  initGroupDetails();
-  initGroupAnalytics();
-  initVueAlerts();
-  initInviteMembersModal();
-  initInviteMembersTrigger();
-});
+leaveByUrl('group');
+initGroupDetails();
+initGroupAnalytics();
+initVueAlerts();
+initInviteMembersModal();
+initInviteMembersTrigger();

ee/app/assets/javascripts/pages/groups/wikis/index.js

 import initWikis from '~/pages/shared/wikis';
 
-document.addEventListener('DOMContentLoaded', initWikis);
+initWikis();

ee/app/assets/javascripts/pages/profiles/billings/index.js

 import initSubscriptions from 'ee/billings';
 import PersistentUserCallout from '~/persistent_user_callout';
 
-document.addEventListener('DOMContentLoaded', () => {
-  PersistentUserCallout.factory(document.querySelector('.js-gold-trial-callout'));
-
-  initSubscriptions();
-});
+PersistentUserCallout.factory(document.querySelector('.js-gold-trial-callout'));
+initSubscriptions();

ee/app/assets/javascripts/pages/profiles/slacks/index.js

 import mountAddGitlabSlackApplication from 'ee/add_gitlab_slack_application';
 
-document.addEventListener('DOMContentLoaded', () => mountAddGitlabSlackApplication());
+mountAddGitlabSlackApplication();

ee/app/assets/javascripts/pages/trial_registrations/new/index.js

@@ -6,10 +6,8 @@ import NoEmojiValidator from '~/emoji/no_emoji_validator';
 import SigninTabsMemoizer from '~/pages/sessions/new/signin_tabs_memoizer';
 import UsernameSuggester from './username_suggester';
 
-document.addEventListener('DOMContentLoaded', () => {
-  new UsernameValidator(); // eslint-disable-line no-new
-  new LengthValidator(); // eslint-disable-line no-new
-  new SigninTabsMemoizer(); // eslint-disable-line no-new
-  new NoEmojiValidator(); // eslint-disable-line no-new
-  new UsernameSuggester('new_user_username', ['new_user_first_name', 'new_user_last_name']); // eslint-disable-line no-new
-});
+new UsernameValidator(); // eslint-disable-line no-new
+new LengthValidator(); // eslint-disable-line no-new
+new SigninTabsMemoizer(); // eslint-disable-line no-new
+new NoEmojiValidator(); // eslint-disable-line no-new
+new UsernameSuggester('new_user_username', ['new_user_first_name', 'new_user_last_name']); // eslint-disable-line no-new