make it run with Expo (CRNA)

[sravinet]

I apparently made it work in this fork
https://github.com/sravinet/aws-mobile-appsync-events-starter-react-native

(however there's an issue to be discussed, I think it's not related to this move to Expo)

[undefobj]

Hi can you let us know what the issue is? This example is for web only whereas the React Native sample should run with Expo.