[native] improve BottomSheet component close function

Summary:
As I was working with/testing out the bottom sheet component, I was running into a bug where if I quickly pressed the bottom sheet backdrop again before the bottom sheet was fully open the onChange callback would not get called. This meant that I was unable to navigate back away from the user profile bottom sheet screen and I would be stuck.

I read through the docs again and I actually found a better prop called onDismiss that just always get called whenever the bottom sheet gets dismissed regardless if the bottom sheet was fully opened or not.

https://gorhom.github.io/react-native-bottom-sheet/modal/props#ondismiss

With onDismiss we can just pass in the onClosed callback prop making the implementation a lot more simple!

Depends on D9258

Test Plan:
Confirmed that when I press the bottomsheet backdrop before the bottomsheet fully opens, I can successfully navigate back when the bottom sheet dismisses

Reviewers: atul, inka

Reviewed By: atul

Subscribers: ashoat, tomek

Differential Revision: https://phab.comm.dev/D9260