Email validation is not modified properly for admin users

[hitotch]

createAdmin() is using validator() and it validates no duplicates in users table instead of admins table.
\app\Http\Controllers\Auth\RegisterController.php

This class needs the additional validator like below, and createAdmin() can use it.
protected function adminValidator(array $data)
{
return Validator::make($data, [
'name' => ['required', 'string', 'max:255'],
'email' => ['required', 'string', 'email', 'max:255', 'unique:admins'],
'password' => ['required', 'string', 'min:8', 'confirmed'],
]);
}