Updated Attachments doesn't get published

Attachments aren't get updated when an attachments version increases and the document get's published. It stays on version 1.1.

Steps to reproduce:

1. Create a document with some publication workflow
2. Edit the document in draft
3. Attach some file to the document
4. Publish it, document and attachment are published on the target page
5. Go into draft again, attach an updated version of the previous file
6. Publish it, you will see that the version doesn't increase and the attachment hasn't been updated