Move package details app to details sub-folder

- app.vue
- code_instruction.vue
- information.vue
- installation.vue
- constants.js
- index.js
- update tests path and folder

ee/app/assets/javascripts/pages/projects/packages/packages/show/index.js

-import initPackageDetail from 'ee/packages';
+import initPackageDetail from 'ee/packages/details/';
 
 document.addEventListener('DOMContentLoaded', initPackageDetail);

ee/spec/frontend/packages/components/app_spec.js → ee/spec/frontend/packages/details/components/app_spec.js

 import { mount } from '@vue/test-utils';
 import { GlModal } from '@gitlab/ui';
-import PackagesApp from 'ee/packages/components/app.vue';
-import PackageInformation from 'ee/packages/components/information.vue';
-import PackageInstallation from 'ee/packages/components/installation.vue';
-import { mavenPackage, mavenFiles, npmPackage, npmFiles } from '../mock_data';
+import PackagesApp from 'ee/packages/details/components/app.vue';
+import PackageInformation from 'ee/packages/details/components/information.vue';
+import PackageInstallation from 'ee/packages/details/components/installation.vue';
+import { mavenPackage, mavenFiles, npmPackage, npmFiles } from '../../mock_data';
 
 describe('PackagesApp', () => {
   let wrapper;

ee/spec/frontend/packages/components/code_instruction_spec.js → ee/spec/frontend/packages/details/components/code_instruction_spec.js

 import { mount } from '@vue/test-utils';
-import CodeInstruction from 'ee/packages/components/code_instruction.vue';
+import CodeInstruction from 'ee/packages/details/components/code_instruction.vue';
 
 describe('Package code instruction', () => {
   let wrapper;

ee/spec/frontend/packages/components/information_spec.js → ee/spec/frontend/packages/details/components/information_spec.js

 import { shallowMount } from '@vue/test-utils';
-import PackageInformation from 'ee/packages/components/information.vue';
+import PackageInformation from 'ee/packages/details/components/information.vue';
 
 describe('PackageInformation', () => {
   let wrapper;

ee/spec/frontend/packages/components/installation_spec.js → ee/spec/frontend/packages/details/components/installation_spec.js

 import { mount } from '@vue/test-utils';
-import PackageInstallation from 'ee/packages/components/installation.vue';
+import PackageInstallation from 'ee/packages/details/components/installation.vue';
 
 describe('PackageInstallation', () => {
   let wrapper;

qa/qa/ee/page/project/packages/show.rb

@@ -6,7 +6,7 @@ module QA
       module Project
         module Packages
           class Show < QA::Page::Base
-            view 'ee/app/assets/javascripts/packages/components/app.vue' do
+            view 'ee/app/assets/javascripts/packages/details/components/app.vue' do
               element :delete_button
               element :delete_modal_button
               element :package_information_content