Make the Invite Modal load conditionally

This change makes two components that were previously added 
to all pages, load when needed to reduce bundle size.

Changelog: performance

app/assets/javascripts/contextual_sidebar.js

@@ -2,8 +2,6 @@ import { GlBreakpointInstance as bp, breakpoints } from '@gitlab/ui/dist/utils';
 import $ from 'jquery';
 import { debounce } from 'lodash';
 import { getCookie, setCookie, parseBoolean } from '~/lib/utils/common_utils';
-import initInviteMembersModal from '~/invite_members/init_invite_members_modal';
-import initInviteMembersTrigger from '~/invite_members/init_invite_members_trigger';
 
 export const SIDEBAR_COLLAPSED_CLASS = 'js-sidebar-collapsed';
 
@@ -114,7 +112,26 @@ export default class ContextualSidebar {
       this.toggleCollapsedSidebar(collapse, true);
     }
 
-    initInviteMembersModal();
-    initInviteMembersTrigger();
+    const modalEl = document.querySelector('.js-invite-members-modal');
+    if (modalEl) {
+      import(
+        /* webpackChunkName: 'initInviteMembersModal' */ '~/invite_members/init_invite_members_modal'
+      )
+        .then(({ default: initInviteMembersModal }) => {
+          initInviteMembersModal();
+        })
+        .catch(() => {});
+
+      const inviteTriggers = document.querySelectorAll('.js-invite-members-trigger');
+      if (inviteTriggers) {
+        import(
+          /* webpackChunkName: 'initInviteMembersTrigger' */ '~/invite_members/init_invite_members_trigger'
+        )
+          .then(({ default: initInviteMembersTrigger }) => {
+            initInviteMembersTrigger();
+          })
+          .catch(() => {});
+      }
+    }
   }
 }

app/assets/javascripts/integrations/edit/index.js

 import Vue from 'vue';
+import { GlToast } from '@gitlab/ui';
 import { convertObjectPropsToCamelCase, parseBoolean } from '~/lib/utils/common_utils';
 
 import IntegrationForm from './components/integration_form.vue';
 import { createStore } from './store';
 
+Vue.use(GlToast);
+
 function parseBooleanInData(data) {
   const result = {};
   Object.entries(data).forEach(([key, value]) => {

app/assets/javascripts/pages/projects/learn_gitlab/index/index.js

 import Vue from 'vue';
 import initInviteMembersModal from '~/invite_members/init_invite_members_modal';
+import initInviteMembersTrigger from '~/invite_members/init_invite_members_trigger';
 import { convertObjectPropsToCamelCase } from '~/lib/utils/common_utils';
 import LearnGitlab from '../components/learn_gitlab.vue';
 
@@ -24,5 +25,7 @@ function initLearnGitlab() {
   });
 }
 
-initLearnGitlab();
 initInviteMembersModal();
+initInviteMembersTrigger();
+
+initLearnGitlab();