[native] Add possibility to display nux tip above an item

Summary:
issue: ENG-9039
I initially removed this logic during my refactor, but @ashoat requested adding it back in D12981

Test Plan: Rendered a tip with both above and below. Checked that the triangle is in the correct place, and the animation expands in the right direction

Reviewers: tomek, will

Reviewed By: tomek

Subscribers: ashoat

Differential Revision: https://phab.comm.dev/D13072