Issue description: It seems that item entities thrown into the smeltery don't get properly deleted, causing players to be able to duplicate items.

Versions:

• Minecraft: 1.16.5
• Forge: 36.1.3
• Mantle: 1.6.79
• Tinkers Construct: 3.0.2.73

Confirm below that this issue is not covered on the roadmap or "Whats New?"
There's no sign of this on both the roadmap and what's new.

Can it be reproduced with just Tinkers Construct? If not, list the other mods required to reproduce the issue.
Yes, you can reproduce this with just Tinkers Construct.

Here is the bug in action:

Issue description: It seems that item entities thrown into the smeltery don't get properly deleted, causing players to be able to duplicate items.

Versions:

* Minecraft: 1.16.5

* Forge: 36.1.3

* Mantle: 1.6.79

* Tinkers Construct: 3.0.2.73

Confirm below that this issue is not covered on the roadmap or "Whats New?"
There's no sign of this on both the roadmap and what's new.

Can it be reproduced with just Tinkers Construct? If not, list the other mods required to reproduce the issue.
Yes, you can reproduce this with just Tinkers Construct.

Here is the bug in action:
2021-04-01_16-08-38.mp4

Confirmed dupe item

Fixed in 3.0.2.76