Examples point to an outdated version of `react-sketchapp`
hello! this is my first time trying sketch react app and I have the following issue(s) with the basic setup example (https://github.com/airbnb/react-sketchapp/tree/master/examples/basic-setup)

I'm using: 
- macOS High Sierra 10.13.2
- npm 8.9.3

**Expected behavior:**
Run basic-setup example successfully.

**Observed behavior:**
- everything works fine until "npm run render" command 
- after "npm run render" nothing happens and I get the following errors:

Using Sketch 48.1, I get the behavior of the following issue:
https://github.com/airbnb/react-sketchapp/issues/213

The recommendation of the issue 213 is "downgrade to Sketch 47.1" - which I did.

Now, using version 47.1 I get the behavior of this issue:
https://github.com/airbnb/react-sketchapp/issues/217

`var funcToString = Function.prototype.toString;`

The recommendation of this issue is to upgrade to Sketch Version 48 ;-) which brings me back to issue #213 

**How to reproduce:**
installed a clean version of react-sketch app and run basic-setup

**Sketch version:**
47.1 / 48.1

Any suggestions? :)