Bitstreams listed in the advancedattachment CRIS Layout option are not sorted correctly

[olli-gold]

Describe the bug
If an item has multiple bitstreams attached, the order of those is not reflected correctly on the item page. For instance: https://tore.tuhh.de/entities/product/bc007281-3425-4d41-82f7-c8bbd4a47dcc - On that item you clearly see, that the files should be in sort order and in the database the sort order is stored correctly. But the showableByItem call does not return the files in the correct sort order and I do not see a parameter allowing me to fix that... https://tore.tuhh.de/dspace-cris-server/api/core/bitstreams/search/showableByItem?uuid=bc007281-3425-4d41-82f7-c8bbd4a47dcc&name=ORIGINAL&filterMetadata=dc.title

To Reproduce
Steps to reproduce the behavior:

• Create an item with multiple files and upload them in a wrong sort order (you cannot change the sort order, as far as I saw that, but that's a different problem after all)
• Approve the item
• See the item page, the files will probably be in wrong order.

Expected behavior
I would like to see the files in the correct order, according to the sort order stored in the database (bundle2bitstream.bitstream_order).

Related work
Nothing I am aware of.