Update React and React Native dependencies to get async act

[SophieAu]

The React Native update to 0.61.1 was released in the last few days and it would be great if we could update to it to take advantage of things like async act.

Updating to the new versions should (in theory) not break anything since they are all minor versions. There might be some potential work involved in updating the act calls to allow for async acts (maybe wrapping everything into async act by default?).

[bcarroll22]

That would be awesome, can you submit a PR? Thanks for pointing it out!

[SophieAu]

just opened one here: #61 However I have added a few questions about how to handle the differentiation between using async or sync act in render and fireEvent