title: laravel Key does not exist or is not readable in issue
body: <p>I have copy laravel project from one directory to another directory.</p>
  
  <p>But it is not working after copy the project.</p>
  
  <p>Please help me.</p>
  
  <p>Error:</p>
  
  <pre><code>[2019-01-30 10:35:14] lumen.ERROR: LogicException: Key path "file:///opt/lampp/htdocs/ghomes/backend/storage/oauth-private.key" does not exist or is not readable in /opt/lampp/htdocs/ghomes/backend/vendor/league/oauth2-server/src/CryptKey.php:45
  Stack trace:
  </code></pre>