[native] introduce loading logic to relationship prompt button

Summary:
This diff introduces the loading logic to the relationship prompt button.

Depends on D12595

Test Plan:
Confirmed that the relationship prompt buttons in the user profile show a loading spinner when the action is in progress

Loading state:

Non loading state:

Reviewers: inka, ashoat

Reviewed By: ashoat

Subscribers: ashoat, tomek

Differential Revision: https://phab.comm.dev/D12596