[native] Get rid of userProfileBottomPadding

Summary:
This padding was hardcoded by Ginsu to add additional space at the bottom of the BottomSheet. It is obviated by my work to consider BottomSheetHandle when setting snapPoints.

This diff reduces the padding somewhat, to be consistent with the rest of our BottomSheets.

Depends on D13869

Test Plan: In combination with the rest of the stack, I tested each individual use of our BottomSheet component to make sure that the bottom padding was reasonable. In most cases it was unchanged; in other cases, it was changed to be more consistent with the other BottomSheets in our codebase. In all cases, there was enough padding for the "home pill" at the bottom of the screen

Reviewers: bartek

Reviewed By: bartek

Subscribers: tomek

Differential Revision: https://phab.comm.dev/D13870