title: Why .enableSassLoader() webpack encore doen't work with new symfony5 project
body: <p>After installing new symfony5 project with Webpack encore installed and .enableSassLoader() activated in webpack.config.js when running <code>yarn encore dev</code> I have got the following error message :</p>
  
  <pre><code>............webpack.config.js:57
  
   .enableSassLoader()
   ^
  SyntaxError: Unexpected token '.'
  .........
  .....
  error Command failed with exit code 1.
  
  </code></pre>
  
  <p>I have the same webpack.config.js configuration in another symfony4 project directory in the same Linux ubuntu computer and it works perfectly!</p>
  
  <p>What's wrong?</p>