fix(message-order): consume message by creation order (fifo)

[mazsudo]

Subject

I found out that with backend: sonata.notification.backend.doctrine, messages are consumed in the wrong order for me that should be first in first consumed. It seems that combination of :

• SonataNotificationBundle/src/Entity/MessageManager.php

  Line 209 in ab45a8a

  ->orderBy('m.createdAt');

  , without order implies 'ASC' by default so old message first in the query result

• SonataNotificationBundle/src/Iterator/MessageManagerMessageIterator.php

  Line 126 in ab45a8a

  $this->current = array_pop($this->buffer);

  , array_pop will pop the element off the end of array which means newest message first

For me it should be a First In First Out, but i may be wrong :)

I am targeting this branch, because it's changing the order of message consumption and may have some unwanted side effects on existing projects.

Changelog

### Fixed
Fix order of message handling with doctrine backend (older first)

[OskarStark]

Thank you for the detailed description of this behavior and I share your thoughts! 👍

[mazsudo]

Thanks for your feedback @OskarStark. FI, i'm going to rework this PR to do an orderBy ASC and an array_shift rather than orderBy DESC and array_pop that sounds more like a double negation.
Currently trying to write an explicit unit test to validate the message processing order. Updates will come soon ;)

[OskarStark]

Thank you, I will prevent merging by "Requesting Changes", please ping me when you want an review again 👍 🚀

[mazsudo]

should be good now @OskarStark ;) orderBy ASC + array_shift is clearer for everyone i hope