title: Change the date format for the showLastUpdateTime at the bottom of pages
body: <p>I've added the</p>
  <pre class="lang-js prettyprint-override"><code>          showLastUpdateTime: true,
  </code></pre>
  <p>line to my <code>docusaurus.config.js</code>, and the date is showing at the bottom of documents, but the format is US (which doesn't work for the majority of the world). I need it to be unambiguous, or not 'wrong' :D</p>
  <p>Does anyone know how I can change this?</p>