Add `void` return type in DoctrineSchemaCompilerPass and MessageQueueCollector

[ruudk]

Fixes these deprecations on Symfony 6.3:

Method "Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface::process()" might add "void" as a native return type declaration in the future. Do the same in implementation "Enqueue\Doctrine\DoctrineSchemaCompilerPass" now to avoid errors or add an explicit @return annotation to suppress this message.
Method "Symfony\Component\HttpKernel\DataCollector\DataCollectorInterface::collect()" might add "void" as a native return type declaration in the future. Do the same in implementation "Enqueue\Bundle\Profiler\MessageQueueCollector" now to avoid errors or add an explicit @return annotation to suppress this message.

[ruudk]

@makasim This one is ready for review.

[ruudk]

@makasim I fixed the CS error. If you approve, it's going to be green. Except for 1 failing test that is out of my control. Could you please merge this? Thanks.

[makasim]

Unfortunately, I cannot merge the red build, If it makes to the main it will stay there for a long time, making the whole idea of testing and CI useless.

[ruudk]

Main is already red: https://github.com/php-enqueue/enqueue-dev/commits/master

The error on this PR is the same, so that's what I mean.

Obviously this PR doesn't create new errors 😅

[ruudk]

I give up. The errors in this PR are unrelated to my changes.

[ruudk]

This fails because this project uses PHPStan 0.12, which is outdated. It should be updated to PHPStan ^1.8.