Update React Scripts

[jamesvclements]

Ran into a bug during testing, found the solution has been fixed in the latest Jest following this.

The current version that we're using of react-scripts uses the old Jest v20.

But when React Scripts 2.0 is released it'll have Jest v22 and we can make the fix.

I know there are some bots that will auto-submit outdated dependencies as issues on our board, but I feel like that'd be a bit much. Maybe there's a Slackbot that could post them to a dedicated BarTop channel so we don't have to waste time tracking stuff down that would be fixed with a dependency bump 😄