[MC-196340] Mobs immune to world border damage

Mobs are immune to damage from the world border.

How to reproduce:

Set a damage amount for the world border (/worldborder damage amount 1)
Spawn a mob anywhere
Set the world border distance so the mob is outside it
If the player is in Survival mode, they will take suffocation damage, but the mob will not.

Linked issues

Sorry for the small GUI scale by the way.

And for my bad English (I'm Hungarian), and for commenting multiple times.

Duplicate of MC-55284 which is marked as Works as Intended

Then why did I take damage out there? I'm confused

And yes, it was the border that killed me.