Add groups view to organization

Related to #409029 (closed)
Designs: https://gitlab.com/gitlab-org/gitlab/uploads/a0fc66cf6945ca50008563935c550762/Organization___Groups_and_projects___Groups.png

What does this MR do and why?

The grouptenant scale team is starting to build out an Organization MVC. For more information about what an "Organization" will be see https://docs.gitlab.com/ee/user/organization/

This MR continues to build the Groups and projects page by adding the groups list.

What is currently implemented

• Groups list populated with mock data

What will be implemented in future MRs

• Use real data when GraphQL API is completed - GraphQL changes for organization level group da... (#409311 - closed)
• Add actions dropdown
• Empty state
• Pagination

Screenshots or screen recordings

Desktop

Mobile

How to set up and validate locally

1. Open Rails console
   • bin/rails console
2. Enable the feature flag
   • Feature.enable(:ui_for_organizations)
3. Create an organization
   • FactoryBot.create(:organization, name: 'GitLab', path: 'gitlab')
4. Navigate to /-/organizations/gitlab/groups_and_projects

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.