Add end to end tests about graphql-hooks

[jackdclark]

@Joezo I think we should bring your Next.js example into this repo regardless of whether it's used for end to end tests.

[Joezo]

Yeah I think I agree about it running agains an SSR example. Although anything is better than what we have now.

I'm going to pick this up now and try get something basic pointing at the create-react-app example.

[jackdclark]

The create-react-app example is now deployed with Netlify and we have PR apps enabled for that. The react-browser-hooks package runs testcafe against Netlify using this script, where it waits for the Netlify preview deploy to succeed before running the acceptance tests against that preview app.

We probably want to run our tests against one of the apps that has SSR implemented though for the best coverage?