Crash when assigning item to a custom category if previous category has been deleted

[cy-br]

Addon Version

v0.3.18

World of Warcraft Version

Classic Era (And SoD/Hardcore)

Describe the bug

When adding an item to a custom category when it has been assigned to a previous category that got deleted the addon crashes
It tries to remove the item from the itemlist in the previouscategory where it does not exist.

1 error:

• Existence of previouscategoryfilter is not checked before calling

Steps to reproduce

1. create custom category
2. manually add item to the category (drag and drop)
3. remove custom category
4. manually add item to a different category