Undefined variable $conf with php 8
During an update testrun ...
PHP Warning: Undefined variable $conf in /tmp/update_runner.sh.MBtkgvU64J/install/lib/installer_base.lib.php on line 251
PHP Warning: Trying to access array offset on value of type null in /tmp/update_runner.sh.MBtkgvU64J/install/lib/installer_base.lib.php on line 251