[MC-198242] Sleeping fox model is not centered inside the hitbox

When a fox sleeps, it looks normal, but if you enable F3 + B, it's not because you'll see that model when sleeping is not centered in the hitbox.

Summon a fox, with NoAI and Sleeping set to 1b:
```
/summon fox ~ ~ ~ {NoAI:1b,Sleeping:1b}
```
Enable F3+B
→ ❌ The sleeping fox model is not properly centered within the hitbox

[media]

Attachments

I can confirm for 1.16.2

Can confirm in 21w03a.

Can confirm in 21w07a. Feel free to use the following command to reproduce this issue:

/summon minecraft:fox ~ ~ ~ {NoAI:1b,Sleeping:1b}

Can confirm in 1.18.1.

Can confirm in 1.18.2.

Can confirm in 1.19.

Can confirm in 1.19.2.