[Workflow] Revert deprecation about Registry

[fabpot]

Q	A
Feature PR	symfony/symfony#51976
PR author(s)	@lyrixx
Merged in	6.4

We created this issue to not forget to document this new feature. We would really appreciate if you can help us with this task. If you are not sure how to do it, please ask us and we will help you.

To fix this issue, please create a PR against the 6.4 branch in the symfony-docs repository.

Thank you! 😃

[xabbuh]

we should probably revert #17878

[lyrixx]

I don't think so. I still believe the registry is a bad idea and not performant. Injecting the right workflow is the best option!

[OskarStark]

I think it's better to revert the PR and add this as a note/caution/warning, because many issues were raised on how to achieve sth. which is not possible without injecting the whole registry, isn't it?

I would avoid such questions in the future, if we can solve this by documenting it 🤷‍♂️

[lyrixx]

We discussed with @alexandre-daubois IRL, and the best things to do is to talk about the registry as late as possible with a big warning: "Don't use it, but if you need to use it, here is the solution"