例子： a.js 引入a.css require b.js，b.js引入b.css 打包时a.css里面竟然包含了b.css内容，怎么回事？下面是我的webpack.config.js 配置 ，不知道哪里有问题，请大佬指点

const path = require('path');
const htmlWebpackPlugin = require('html-webpack-plugin');
const cleanWebpackPlugin = require('clean-webpack-plugin');
const MiniCssExtractPlugin = require("mini-css-extract-plugin");


var getHtmlConfig = function (filename,title) {
    return {
        template:'./src/' + filename + '/'+ filename + '.html',
        filename: filename + '.html',
        title:title,
        hash:true,
        chunks:[filename]
    }
}
module.exports = {
    entry: {
        index:'./src/index/index.js',
        test:'./src/test/test.js'
    },
    output: {
        filename: './js/[name].bundle.js',
        path: path.resolve(__dirname,'dist'),
    },
    devServer:{
        contentBase: './dist'
    },
    plugins: [
        new htmlWebpackPlugin(getHtmlConfig("index",'index')),
        new htmlWebpackPlugin(getHtmlConfig("test",'test')),
        new cleanWebpackPlugin(['dist']),
        new MiniCssExtractPlugin({
            filename: "./css/[name].css",
            chunkFilename: "[id].css"
        })
    ],
    module:{
        rules:[
            {
                test: /\.css$/,
                use: [
                    MiniCssExtractPlugin.loader,
                    {
                        loader: "css-loader",
                        options: {
                          minimize: true
                        }
                    },
                ]
            },
            {
                test:/\.(png|svg|jpg|gif)$/,
                use:[
                    'file-loader'
                ]
            },
            {
                test: /\.(woff|woff2|eot|ttf|otf)$/,
                use:[
                    'file-loader'
                ]
            }
        ]
    }