Symfony 7.0 compatibility

[b1rdex]

The bundle is not compatible with 7.0

PHP Fatal error:  Declaration of Jsvrcek\Bundle\IcsBundle\DependencyInjection\Configuration::getConfigTreeBuilder()
must be compatible with Symfony\Component\Config\Definition\ConfigurationInterface::getConfigTreeBuilder():
Symfony\Component\Config\Definition\Builder\TreeBuilder

Workaround:

1. remove composer dependency jsvrcek/ics-bundle
2. add composer dependency jsvrcek/ics
3. add these lines to services.yml (to services section):

    Jsvrcek\ICS\CalendarExport:
    Jsvrcek\ICS\CalendarStream:
    Jsvrcek\ICS\Utility\Formatter: