Annotations are not always synced from server during fast sync

[Server does not consider annotation changes as article changes](https://github.com/wallabag/wallabag/issues/4345). That's why fast update does not receive articles with only annotations changed.

Client-to-server sync is fine.

Workarounds:
* Full sync.
* Doing other changes to article.
For example, if you create an annotation, then favorite and immediately unfavorite the article, the article (and the new annotation) will be synced to the client with fast sync.
Marking read/unread, changing title, changing tags work to.