[native] [22/34] ReactNav6: Move keyboardHandlingEnabled to StackOptions

Summary:
Context on change here.

Depends on D5414

Test Plan: Flow + ran the app on my phone and played around with it

Reviewers: atul, tomek, bartek

Reviewed By: atul

Subscribers: abosh

Differential Revision: https://phab.comm.dev/D5415