Fix the Docusaurus trailing slash issue in self-host

Create a file called static/js/fix-location.js with:

if (window && window.location && window.location.pathname.endsWith('/') && window.location.pathname !== '/') {
  window.history.replaceState('', '', window.location.pathname.substr(0, window.location.pathname.length - 1))
}

Load this file as static JS file in docusaurus.config.js:

  scripts: [
    {
      src: '/js/fix-location.js',
      async: false,
      defer: false,
    }
   ],

ref: https://github.com/facebook/docusaurus/issues/2394#issuecomment-630638096