Update to PHP 8.1 and Symfony 6
Happens in branch https://github.com/netresearch/timetracker/tree/php81_symfony6
Update to PHP 8.2 and Symfony 4
Update to PHP 8.4 and Symfony 6
Update to PHP 8.4 and Symfony 7
Update to PHP 8.5 and Symfony 8
Happens in branch https://github.com/netresearch/timetracker/tree/main