[native] [2/34] ReactNav6: added new path property to Route prop

Summary:
Context on change here.

The changes to our codebase were necessary because we were using the wrong type from the libdef.

Depends on D5394

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/D5395