Update Webpack #49
Description
Currently we are using v4.42.0 of Webpack. It's not too old but since the model manager is not an example project but rather a real useful tool for production, it would be a good idea to future proof it by upgrading the configuration.
Some eslint plugins for typescript must be changed (along with their config and eslint-loader) as they are depreciated, two component of react-dev-tools are missing (WatchMissingNodeModulesPlugin and typescriptFormatter), pnp is now included with webpack 5, so the config needs to be seriously upgraded to work with our plugins and a newer version of Webpack and don't even get me started about postcss dependencies debacle.
I made a test with #46 but it didn't went well as I'm not versed enough with webpack and it's ecosystem to really make the necessary changes.