title: Html webpack plugin html file not generated
body: <p>I just started with webpack, and I want to automatically generate index.html file using html-webpack-plugin.</p>
  
  <p>My webpack.config.js:</p>
  
  <pre><code>var path = require('path');
  var webpack = require('webpack');
  var HtmlWebpackPlugin = require('html-webpack-plugin');
  
  module.exports = {
      plugins: [
          new HtmlWebpackPlugin({
              hash: true
          })
      ]
  }
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/i4kSw.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/i4kSw.jpg" alt="enter image description here"></a></p>
  
  <p>I execute "npm run dev" equals to webpack --mode development, and only 1 file generated "main.js".</p>
  
  <p>I don't see any html files, could you please help me?</p>
  
  <p>webpack: 4.5.0
  html-webpack-plugin: 3.2.0</p>
  
  <p>Thanks in advance</p>