Add group/project interdependencies

Overview

There are certain group/project interdependencies that can be detected via the API, e.g.

• Project fork relationships i.e. forked_from_project

  If the project is a fork, the forked_from_project field appears in the response.

• Projects shared with groups i.e. group's shared projects - shared_with_groups
  • NOTE: This field is available via both individual (/api/v4/projects/:id) and bulk (/api/v4/projects) API responses. The bulk one is already a pain point for API response times. The only reason it's still available is because removing it would be a breaking change.
• Groups shared with groups - shared_with_groups
  • NOTE: This field is only available via individual group API responses (/api/v4/groups/:id)

These should be added as separate columns and represented as source full_path (group) i.e. path_with_namespace (project).