Shulker boxes and bundles drop their items twice when thrown into a lava cauldron

The bug

With the new snapshot 20w51a shulker boxes and bundles drop their items twice when thrown into a lava cauldron, instead of only once, allowing you to duplicate items.

How to reproduce:

1. Place a cauldron
2. Fill it with lava
3. Place a shulker box
4. Put an item in it
5. Throw the shulker box into the cauldron
   You get the item twice.