Read the React Native version from the react-native's package.json (#52509)

Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/52509

When building the CI Workflow to build React Native prebuilds, we were reading the react-native's version from the root package.json. This package.json is not updated by the release script, so the version is always 1000.
This makes the build process fail for stable releases.

With this change, we read the version from the right package.json file

## Changelog:
[Internal] - Read React Native version from the right package.json file

Reviewed By: cortinico

Differential Revision: D78007906

fbshipit-source-id: 35f868a1c203245fdcf518ee81957352e3ab1de7