Add no results found message to transfer group dropdown

What does this MR do and why?

Related to #385786 (closed)

Currently if you search in the transfer group dropdown and the API returns no results the dropdown doesn't render anything and this causes confusion and some funky behavior.

This MR adds an empty state to the dropdown.

Screenshots or screen recordings

Before	After

How to set up and validate locally

1. Navigate to a group -> Settings -> General -> Advanced -> Transfer group
2. Open the dropdown and type zzzz

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.