Update eslint-plugin-react 5.1.1 -> 6.1.2
Update eslint-plugin-react 5.1.1 -> 6.1.2

We barely use this as a devDependency, but since it is the only on that
hasn't been updated I figured I might as well just do it.

trotzig/import-js,Galooshi/import-js,trotzig/import-js,trotzig/import-js