Zombified Piglin's look like old zombie pigmen

Steps to reproduce

1. Apply a resource pack that has not been updated since the nether update in either Global Resources or the resources for a particular world.
2. Load the world
3. Spawn a zombified piglin.

Expected result

You get a zombified piglin.

Observed result

You get a zombie pigman.

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Some players see the zombified piglin model but the spawn egg says "zombie piglin" , while other players see the opposite.

Other players see the zombie piglin model but the spawn egg says "zombified piglin"