[native] Disable stack gestures while editing messages

Summary:
See ENG-4412 to see the bug this diff solves.

I was unable to disable gestures using gestureEnabled for some reason. This appears to be a React Navigation bug reported here. I tried disabling gestures via options for MessageList, screenOptions for Chat.Navigator, and even using an effect that calls setOptions from ChatInputBar. None of them worked.

Instead, I found that setting gestureResponseDistance to 0 has the desired effect (disabling gestures).

Test Plan: Confirm that I can no longer use gestures to go back while in edit mode

Reviewers: atul, tomek, kamil

Reviewed By: kamil

Differential Revision: https://phab.comm.dev/D8543