Panel: The server owner search bar seems to only work on the email field

[jordanamr]

Background (please complete the following information):

• Panel or Daemon: Panel
• Version of Panel/Daemon: 1.0.0-rc.6
• Server's OS: CentOS 8
• Your Computer's OS & Browser: Windows 10, Edge Chromium

Describe the bug
We cannot search for a server owner using first name, last name or username, it only works using the email.

To Reproduce
Steps to reproduce the behavior:

1. Create a new server
2. In the "server owner" field, try using either the user first name or username.
3. Does not work. It only works if you type a word contained in the email field of that user.

Expected behavior
I should be able to type the user's username or first name to find him.

[gabefraser]

Looks to be a pretty simple fix. It's just adding some additional fields into the allowedFilters array:

From: ['email']
To: ['username', 'email', 'name_first', 'name_last']

https://github.com/pterodactyl/panel/blob/develop/app/Http/Controllers/Admin/UserController.php#L188

[DaneEveritt]

This is intentional for the time being and will be addressed by the admin area re-write.