Fix HMR by providing 'Access-Control-Allow-Origin': '*' header to devServer config

[DethAriel]

This issue is a:

• Bug report

Hot Module replacement for nwb server-react-app (and maybe other commands) stopped working after webpack-dev-middleware version was updated, see the cause here. The fix is to add the following to the devServer config:

{
  devServer: {
    headers: {
      'Access-Control-Allow-Origin': '*'
    }
  }
}