Fixes #4703 Disable preview for item leveled list

This is a fix for #4703 (closed) which states that preview makes no sense for item leveled lists (there's already some code here for creature leveled lists, but I'm wondering if this will always fallback on the hard coded-model?).

The issue is mentioned as related to #4705 (closed), however I think the fix for that would be a bit different.

It's a bit of a band-aid fix for the specific issue mentioned in the report, so I'm looking for some feedback.

This is also my first ever PR/MR for an open sourced project, so I went with something relatively small. However, I'm quite used to the process in my professional life.

I'm happy to help out in any way I can!