svgの使用するためにwebpackにおける設定

webpackでsvgを使用するためにwebpack.config.jsを設定しているのですが、上手く表示されません。ターミナルではエラーは発生しておらず、原因がわかりません。

webpack.config.jsのコードは公式レファレンスから拝借してます。

"devDependencies": {
    "babel-core": "^6.26.3",
    "babel-loader": "^7.1.5",
    "babel-preset-env": "^1.7.0",
    "css-loader": "^2.1.1",
    "html-webpack-plugin": "^3.2.0",
    "node-sass": "^4.12.0",
    "path": "^0.12.7",
    "sass-loader": "^7.1.0",
    "style-loader": "^0.23.1",
    "svg-sprite-webpack-plugin": "^1.0.4",
    "webpack": "^4.31.0",
    "webpack-cli": "^3.3.2",
    "webpack-dev-server": "^3.3.1",
    "webpack-isomorphic-tools": "^3.0.6"
  }

html
1<svg class="user_icon icon__small">
2  <use xlink:href="./img/icons-defs.svg#icon-user"></use>
3</svg>

Javascript
1const path = require('path');
2const HtmlWebpackPlugin = require('html-webpack-plugin');
3const IconPlugin = require('svg-sprite-webpack-plugin').plugin;
4const iconPlugin = new IconPlugin('icons-[defs].svg');
5const iconParser = require('svg-sprite-webpack-plugin').webpackIsomorphicParser;
6
7module.exports = {
8    entry: './src/js/index.js',
9    output: {
10        filename: 'bundle.js'
11    },
12    module: {
13        rules: [
14            {
15                test: /.scss$/,
16                use: [
17                    "style-loader", // creates style nodes from JS strings
18                    "css-loader", // translates CSS into CommonJS
19                    "sass-loader" // compiles Sass to CSS, using Node Sass by default
20                ]
21            },
22            {
23                test: /.js$/,
24                exclude: /node_modules/,
25                use: {
26                    loader: 'babel-loader'
27                }
28            },
29            {
30                test: /.svg$/,
31                loader: iconPlugin.extract(),
32            }
33        ]
34    },
35    devServer: {
36        contentBase: './dist'
37    },
38    plugins: [
39        new HtmlWebpackPlugin({
40            filename: 'index.html',
41            template: './src/index.html'
42        }),
43        new IconPlugin('icons-[defs].svg', {
44            options: {
45                assets: {
46                    svg: {
47                        extension: 'svg',
48                        parser: iconParser
49                    }
50                }
51            }
52        })
53    ]
54}