title: need to add /public/ to the packages assets root path of laravel backpack
body: <p>My Laravel installation is in a subfolder/subapp. I then installed Backpack 4.1. Url of backpack login is something like <a href="http://example.test/laravel/admin/login" rel="nofollow noreferrer">http://example.test/laravel/admin/login</a>.</p>
  <p>My Laravel is running fine as a second app in the subfolder (I used nginx to manage the main app and the laravel app as second app in sub-folder).</p>
  <p>But the backpack page is not loading the CSS and JS files as /public/ of laravel is missing in the path.</p>
  <p>I tried to add ASSET_URL=public in .env of laravel. But did not work.</p>
  <p>Need help on this.</p>
  <p>Thank you.</p>