[Messenger] Document #[AsMessage] attribute

[pounard]

Fixes #20002

Document the newly merged #[AsMessage] attribute symfony/symfony#57507

[MrYamous]

I think we should also add it to the Attribute Overwiew page

[pounard]

Sorry, I took a few days off. I'll be back in a few days for fixing this.

[javiereguiluz]

@pounard friendly ping. This is almost ready, so I hope you can find some time to finish it. Thanks a lot!

[pounard]

@pounard friendly ping. This is almost ready, so I hope you can find some time to finish it. Thanks a lot!

I'm sorry, I spent more time off work than it was initially planned. I will be back in september.

[pounard]

@MrYamous

I think we should also add it to the Attribute Overwiew page

I just added it, thanks for pointing this.

[pounard]

@javiereguiluz Ready for review once again! Sorry for keeping this waiting.

[pounard]

I have really no idea why the "Code Blocks" action fails. Any ideas?

[javiereguiluz]

Pierre, thanks for contributing this feature and its docs.

While merging, I reworded your contribution (See d926bbb). It looks like I changed everything ... but that's not true. I reused all your original contents, but merged them into the previous section. I did this because in the rest of the docs we always display the PHP attributes alongside the YAML/XML/PHP config files. Thanks!