Force transfer project dropdown to display at top

What does this MR do and why?

Forces transfer project dropdown to display on top (fixes Project/Group Transfer Namespace Dropdown Posit... (#381376 - closed))

Screenshots or screen recordings

Before	After

How to set up and validate locally

Go to transfer project settings (ie http://gdk.test:3000/gitlab-org/gitlab-test/edit#js-project-advanced-settings)

Links

• ✂️ UX Paper Cuts 18.1 → Mixed milestone (#513102 - closed)
• Project/Group Transfer Namespace Dropdown Posit... (#381376 - closed)