Plugin has unexpected effects if not added first

[Alf Eaton]

Issue description

workbox-webpack-plugin has an option to add a versioned workbox folder to the output directory.

When clean-webpack-plugin v3 is in the plugins list before workbox-webpack-plugin everything works as expected, but when it's in the plugins list after workbox-webpack-plugin the versioned workbox folder is missing.

With clean-webpack-plugin v2 the workbox folder is always present.

Webpack Config

const { CleanWebpackPlugin } = require("clean-webpack-plugin");
const WorkboxWebpackPlugin = require("workbox-webpack-plugin");

module.exports = {
  mode: "production",
  plugins: [
    new CleanWebpackPlugin(), // workbox directory is present
    new WorkboxWebpackPlugin.GenerateSW({
      importWorkboxFrom: "local"
    })
    // new CleanWebpackPlugin() // workbox directory is missing
  ]
};

Environment

    clean-webpack-plugin: ^3.0.0 => 3.0.0 
    webpack: ^4.35.0 => 4.35.0 
    workbox-webpack-plugin: ^4.3.1 => 4.3.1 

Repository to reproduce the issue: https://github.com/hubgit/clean-workbox-example

[Chris Blossom]

Thanks for the repo! I think the right thing to do here is document this behavior in the readme.

Basically if you are using a webpack that modifies files directly instead of letting webpack do the work this will be an issue.