Mobs sit too low on the raft

Summary:
Mobs are too low on the raft. Because of this, they are partially "immersed" in the raft.

Steps to reproduce:

1. Place the raft.
2. Put the mob in the raft (for example axolotl).

Observed results:
Mob sits in a raft, not on the raft.

Expected results:
Mob sits on the raft, not immersed in it.

Screenshots: