Steps to reproduce the issue

Set the level of error reporting to 'Maximum'.
Open Patch Tester.
Click the button Fetch Data.

Expected result

No error messages.

Actual result

A Deprecated error is displayed at the top of the page administrator/index.php?option=com_patchtester
( ! ) Deprecated: strtoupper(): Passing null to parameter #1 ($string) of type string is deprecated in C:\www\joomla41\libraries\src\MVC\Model\ListModel.php on line 586

The same Deprecated error is displayed at the top of the modal 'Fetching Github Data'.

System information (as much as possible)

Joomla 4.1.5-dev of 1 June, Wampserver 3.2.9 with PHP 8.1.6

Additional comments

This Deprecated messages is not displayed when using PHP 8.0.15