draft: Fix GitHub pipeline

[Rubc]

1. Update Somfony flex due to this error:

- Installing symfony/flex (v1.17.2): Extracting archive PHP Fatal error: Declaration of Symfony\Flex\Command\RemoveCommand::execute(Symfony\Component\Console\Input\InputInterface $input, Symfony\Component\Console\Output\OutputInterface $output) must be compatible with Composer\Command\RemoveCommand::execute(Symfony\Component\Console\Input\InputInterface $input, Symfony\Component\Console\Output\OutputInterface $output): int in /home/runner/work/fireping/fireping/vendor/symfony/flex/src/Command/RemoveCommand.php on line 30 Fatal error: Declaration of Symfony\Flex\Command\RemoveCommand::execute(Symfony\Component\Console\Input\InputInterface $input, Symfony\Component\Console\Output\OutputInterface $output) must be compatible with Composer\Command\RemoveCommand::execute(Symfony\Component\Console\Input\InputInterface $input, Symfony\Component\Console\Output\OutputInterface $output): int in /home/runner/work/fireping/fireping/vendor/symfony/flex/src/Command/RemoveCommand.php on line 30 Error: Process completed with exit code 255.

2. Use Phpunit instead of Simple phpunit due to build errors
3. Throw a warning when the Symfony security check fails