Add projects list to organization groups and projects page

What does this MR do and why?

Related to #409030 (closed)

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 starts building out the projects view on the "Groups and projects" page. For full designs see #406613 (closed)

What this MR does

• Sets up GraphQL resolver with mock response
  • The real GraphQL API will be setup in #409312 (closed) but until then we will use mock data so we can start building out the frontend
• Renders the projects_list.vue component

What will be done in future MRs

• Add filtered search bar
• Add dropdown to change between Projects and Groups
• Add sort
• Add pagination
• Add Edit and Delete actions

Screenshots or screen recordings

Desktop

Mobile

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Error

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.