Enable devServer.stats.colors by default (#2937)
Enable devServer.stats.colors by default (#2937)

The webpack-dev-server changed the default option for
devServer.stats.colors from true to false in a recent version:
https://github.com/webpack/webpack-dev-server/pull/2660/files#r447299960

This PR sets the default Webpacker 6 devServer.stats.colors to true to
preserve this behavior across the upgrade.
rails/webpacker,rails/webpacker