Support RN 0.64.1 🙏 

## Expected results

v0.64.1 of React Native got released and is needed to work properly on Xcode 12.5, so current latest template doesn't work on that version of Xcode (https://github.com/facebook/react-native/releases/tag/v0.64.1).

## Why it is needed

To have an updated TypeScript template for the new React Native version and support the latest Xcode version.

