Conditionally import loads the projects dropdown when opened.

What does this MR do?

EE MR of https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/15995

Are there points in the code the reviewer needs to double check?

No

Why was this MR needed?

EE MR of https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/15995

Screenshots (if relevant)

None

Does this MR meet the acceptance criteria?

• Review
  • Has been reviewed by Frontend
• Conform by the merge request performance guides
• Conform by the style guides
• Squashed related commits together
• Internationalization required/considered
• If paid feature, have we considered GitLab.com plan and how it works for groups and is there a design for promoting it to users who aren't on the correct plan

What are the relevant issue numbers?

Part of https://gitlab.com/gitlab-org/gitlab-ce/issues/38869.