Upgrading a world with empty item display entities logs error

Upgrading a world with empty item_display entity logs error. Relates to MC-270867

Steps to Reproduce

1. In 1.20.4, create a world.
2. Spawn an item display: /summon item_display
3. Upgrade the world to 1.20.5-rc1.

Expected Result
No error is logged.

Actual Result
An error is logged:

[21:46:54] [Server thread/ERROR]: Tried to load invalid item: 'Item must not be minecraft:air'

Attached a world with many empty item display entities.