Fix xplat sync (#29833)

## Overview

The clever trick in https://github.com/facebook/react/pull/29799 turns
out to not work because signedsource includes the generated hash in the
header. Reverts back to checking git diff, filtering out the REVISION
file and `@generated` headers.

Ricky committed 1y ago

f81d5ee219848c7a02c0afdbd46fc1cedcc72df0

Parent: a532d91

Committed by GitHub <[email protected]> on 6/10/2024, 5:24:45 PM