Add MR Analytics skeleton code

Introduce the base / bootstrapping code needed for the
Merge Request Analytics page.

This is an MVC MR.

ee/app/assets/javascripts/analytics/merge_request_analytics/components/app.vue

+<script>
+export default {
+  name: 'MergeRequestAnalyticsApp',
+};
+</script>
+<template>
+  <div>
+    <h3 data-testid="pageTitle">{{ __('Merge Request Analytics') }}</h3>
+  </div>
+</template>

ee/app/assets/javascripts/analytics/merge_request_analytics/index.js

+import Vue from 'vue';
+import MergeRequestAnalyticsApp from './components/app.vue';
+
+export default () => {
+  const el = document.querySelector('#js-merge-request-analytics-app');
+
+  if (!el) return false;
+
+  return new Vue({
+    el,
+    name: 'MergeRequestAnalyticsApp',
+    render: createElement => createElement(MergeRequestAnalyticsApp),
+  });
+};

ee/app/assets/javascripts/pages/groups/analytics/merge_request_analytics/index.js

+import initMergeRequestAnalyticsApp from 'ee/analytics/merge_request_analytics';
+
+document.addEventListener('DOMContentLoaded', initMergeRequestAnalyticsApp);

ee/app/views/groups/analytics/merge_request_analytics/show.html.haml

+- page_title _('Merge Request Analytics')
+
+#js-merge-request-analytics-app

ee/spec/frontend/analytics/merge_request_analytics/components/app_spec.js

+import { shallowMount } from '@vue/test-utils';
+import MergeRequestAnalyticsApp from 'ee/analytics/merge_request_analytics/components/app.vue';
+
+describe('MergeRequestAnalyticsApp', () => {
+  let wrapper;
+
+  const createComponent = () => {
+    wrapper = shallowMount(MergeRequestAnalyticsApp);
+  };
+
+  beforeEach(() => {
+    createComponent();
+  });
+
+  afterEach(() => {
+    wrapper.destroy();
+    wrapper = null;
+  });
+
+  it('displays the page title', () => {
+    const pageTitle = wrapper.find('[data-testid="pageTitle"').text();
+
+    expect(pageTitle).toEqual('Merge Request Analytics');
+  });
+});

locale/gitlab.pot

@@ -14672,6 +14672,9 @@ msgstr ""
 msgid "Merge Request"
 msgstr ""
 
+msgid "Merge Request Analytics"
+msgstr ""
+
 msgid "Merge Request Approvals"
 msgstr ""