title: MiniCssExtractPlugin doesn't link with my html file
body: <p>When i Webpack my project using MiniCssExtractPlugin to separate css into files, it creates  the main.css file but never write the link into my html file.</p>
  
  <p>Here is my webpack.config.js :</p>
  
  <pre><code>const webpack = require("webpack");
  const path = require("path");
  const UglifyJsPlugin = require("uglifyjs-webpack-plugin")
  const dev = process.env.NODE_ENV ==="dev"
  const MiniCssExtractPlugin = require('mini-css-extract-plugin')
  let cssloaders = [MiniCssExtractPlugin.loader, {loader: 'css-loader', options:{importLoaders: 2, modules: true } } ]
  
  
  if(!dev) {
      cssloaders.push( {
          loader: 'postcss-loader',
          options : {
  
              plugins: (loader) =&gt; [
  
  
                require('autoprefixer')( { browsers : ['last 2 versions', 'ie &gt; 8'] 
                }),
              ]
          },
  })
  
  }
  
  let config = {
    mode : 'none',
    entry:  "./assets/js/app.js" ,
    output: {
      path: path.resolve(__dirname, "./dist"),
      filename: "bundle.js",
      publicPath: "/wp/dist/"
    }, 
    devtool : dev ? "cheap-module-eval-source-map" : "source-map",
    watch : dev,
    module : {
      rules : [
        {
          test : /\.js$/,
          exclude: /(node_modules|bower_components)/,
  
          use : [
              'babel-loader'
          ]
        },
        {
            test : /\.css$/,
            use: cssloaders
        },
        {
            test : /\.scss$/,
            use: 
          [
            ...cssloaders,
            'sass-loader'
          ]
          ,
        },
  
      ]
    },
    plugins : [
      new MiniCssExtractPlugin({
        filename : '[name].css',
        chunkFilename: "[id].css"
  
      })
  
    ],
    optimization : {
      minimize : !dev
    }
  
  }
  if(!dev){
    config.plugins.push(new UglifyJsPlugin({
      sourceMap : true
    }))
  }
  
  module.exports = config;
  </code></pre>
  
  <p>So the loaders are in correct order : postcss-loader (if not in dev), sass-loader (for scss test), css-loader and MiniCssExtractPlugin.</p>
  
  <p>When I webpack, the main.css fil is well emitted, but the html file doesn't have the link href in the head written...so there is no css :-)</p>
  
  <pre><code>bundle.js  4.85 KiB       0  [emitted]  main
   main.css  67 bytes       0  [emitted]  main
  </code></pre>
  
  <p>I think i miss something ? </p>
  
  <p>Thank you in advance !</p>