updates needed to Setup section

[shkeating]

A couple of changes have occurred since the copy was written in the Setup section:

1. The TINA_CMS_ID is labelled as a Content (Readonly) Token in Tina Cloud.
2. The versions of tina in this repo are behind what Tina now requires to set up a new project in Tina cloud. If someone follows the instructions here, the netlify deploy will fail repeadly with the error The local GraphQL schema doesn't match the remote GraphQL schema. To fix this I had to run an npm install and npm audit fix --force and then push to get Netlify to deploy successfully.

I still figured it out in the end, but had to do a little deductive reasoning and peeking through the Tina docs to sort it out. Might be worth updating your readme to reflect these. Otherwise though, very straightforward instructions. Thanks!

[danurbanowicz]

Thanks @shkeating for the heads up! Would you be willing to put these changes to the setup text in a PR? My memory of how Tina CMS works is pretty hazy and need to revisit it when I get a chance.