raw-editor: upgrade json editing tool

[CarlosNZ]

Heya, great project, looks very interesting!

I just stumbled upon it as you're using one of my packages for the raw editor: https://github.com/CarlosNZ/json-edit-react

I noticed the "expand" icon is getting a bit "clipped" on the left when it's in the open state:

So just wanted to let you know that this issue has been fixed so you should be able to update to the latest version (1.15.9) to make this look a little nicer :)

All the best.