Failed to create admin user during bootstrap due to PASSWORD_MINLENGTH

On first boot, it tries to create admin user with 'admin' as password, which fails since it is shorter than default PASSWORD_MINLENGTH (8):

```
Fatal error: Uncaught exception 'Exception' with message 'Warning, password is empty or too short!' in /var/www/localhost/htdocs/ajaxplorer/core/src/core/classes/class.AuthService.php:654
```