webpackでurl-loaderを用いて画像ファイルのバンドルができない

経緯

webpackには、CSSファイル内の画像パスをbase64に変換して挿入してくれる「url-loader」というのがあると知って、それを利用しようとしたのですがうまくいきません。

ビルド時には特にエラーは出ておらず、いろいろ試したのですが、一向に変換してくれません。
お手数ですが、ご助言いただけると幸いです。

環境

Windows 10 Home
Node.js v11.7.0
npm v6.5.0
webpack v4.29.0

package.json

json
1{
2  "name": "aaaa",
3  "version": "1.0.0",
4  "description": "",
5  "main": "index.js",
6  "scripts": {
7    "test": "echo \"Error: no test specified\" && exit 1",
8    "build": "webpack",
9    "watch": "webpack --watch"
10  },
11  "author": "",
12  "license": "ISC",
13  "devDependencies": {
14    "autoprefixer": "^9.4.6",
15    "css-loader": "^2.1.0",
16    "cssnano": "^4.1.8",
17    "file-loader": "^3.0.1",
18    "mini-css-extract-plugin": "^0.5.0",
19    "node-sass": "^4.11.0",
20    "postcss-loader": "^3.0.0",
21    "sass-loader": "^7.1.0",
22    "url-loader": "^1.1.2",
23    "webpack": "^4.29.0",
24    "webpack-cli": "^3.2.1"
25  }
26}

webpack.config.js

JavaScript
1const MODE = 'development';
2const MiniCssExtractPlugin = require('mini-css-extract-plugin');
3const enabledSourceMap = (MODE === 'development');
4const devtool_value = enabledSourceMap ? "inline-source-map" : "";
5
6module.exports = {
7
8  mode: MODE,
9
10  devtool: devtool_value,
11
12  module: {
13    rules: [
14      {
15        test: /.scss/,
16        use: [
17          MiniCssExtractPlugin.loader,
18          {
19            loader: 'css-loader',
20            options: {
21              url: false,
22              sourceMap: enabledSourceMap,
23              importLoaders: 2
24            },
25          },
26          {
27            loader: 'postcss-loader',
28            options: {
29              sourceMap: enabledSourceMap,
30              plugins: [
31                require('autoprefixer')({
32                  browsers: [
33                    "last 2 version",
34                    "> 0.2%",
35                  ],
36                }),
37                require('cssnano')(),
38              ]
39            },
40          },
41          {
42            loader: 'sass-loader',
43            options: {
44              sourceMap: enabledSourceMap,
45            }
46          },
47        ],
48      },
49      {
50        test: /.(gif|png|jpg|eot|wof|woff|woff2|ttf|svg)$/,
51        loader: 'url-loader',
52      },
53    ],
54  },
55  plugins: [
56    new MiniCssExtractPlugin({
57      filename: 'style.min.css',
58    })
59  ],
60};

style.min.css

css
1.icon{background-image:url(icon.png)}
2
3/*# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbIndlYnBhY2s6Ly8vLi9zcmMvc2Nzcy9zdHlsZS5zY3NzIl0sIm5hbWVzIjpbXSwibWFwcGluZ3MiOiJBQUVBLE1BQ0UsOEJBQStCLEMiLCJmaWxlIjoic3R5bGUubWluLmNzcyIsInNvdXJjZXNDb250ZW50IjpbIkBjaGFyc2V0IFwiVVRGLThcIjtcclxuXHJcbi5pY29uIHtcclxuICBiYWNrZ3JvdW5kLWltYWdlOiB1cmwoaWNvbi5wbmcpO1xyXG59XHJcbiJdLCJzb3VyY2VSb290IjoiIn0=*/

コマンドプロンプト内の表示

cmd
1Hash: 9882774b60180a36fa72
2Version: webpack 4.29.0
3Time: 879ms
4Built at: 2019-01-25 16:35:12
5        Asset       Size  Chunks             Chunk Names
6      main.js   9.39 KiB    main  [emitted]  main
7style.min.css  437 bytes    main  [emitted]  main
8Entrypoint main = style.min.css main.js
9[./src/index.js] 29 bytes {main} [built]
10[./src/scss/style.scss] 39 bytes {main} [built]
11    + 1 hidden module
12Child mini-css-extract-plugin node_modules/css-loader/dist/cjs.js??ref--4-1!node_modules/postcss-loader/src/index.js??ref--4-2!node_modules/sass-loader/lib/loader.js??ref--4-3!src/scss/style.scss:
13    Entrypoint mini-css-extract-plugin = *
14    [./node_modules/css-loader/dist/cjs.js?!./node_modules/postcss-loader/src/index.js?!./node_modules/sass-loader/lib/loader.js?!./src/scss/style.scss] ./node_modules/css-loader/dist/cjs.js??ref--4-1!./node_modules/postcss-loader/src??ref--4-2!./node_modules/sass-loader/lib/loader.js??ref--4-3!./src/scss/style.scss 462 bytes {mini-css-extract-plugin} [built]
15        + 1 hidden module