Using a datapack and resourcepack to apply armor trim to items that are not armor does not apply the armor trim to the item as expected.

Steps to reproduce:

1) load a datapack and resourcepack that adds armor trim functionality to an item that isn't armor (this guide for how to do this or use theirs from the github: https://minecraft.wiki/w/Tutorials/Adding_custom_trims#Custom_trimmable_items)

2) attempt to apply armor trim to the item

3) observe that the item does not appear to change in the output slot, but the rendered preview of the item in the gui has changed to the expected vanilla result