Bugfix/php8.3

[tswagger]

Parent class of SparkCommand.php -> Symfony\Component\Console\Command\Command requires a return type specified. Added required return type.

The lack of return type was causing issues with php 8.3

[insign]

@jenssegers can you please check this?

PHP 8.4

oot@1c8aca00977a:/var/www/html#  php vendor/bin/optimus spark

Fatal error: Declaration of Jenssegers\Optimus\Commands\SparkCommand::execute(Symfony\Component\Console\Input\InputInterface $input, Symfony\Component\Console\Output\OutputInterface $output) must be compatible with Symfony\Component\Console\Command\Command::execute(Symfony\Component\Console\Input\InputInterface $input, Symfony\Component\Console\Output\OutputInterface $output): int in /var/www/html/vendor/jenssegers/optimus/src/Commands/SparkCommand.php on line 40