Saddled pigs / horses still move when in their death animation

The bug

When a saddled pig with a carrot on a stick or a horse dies, they can still move when in their death animation.

How to reproduce

1. Summon a horse and mount it

   /summon horse ~ ~ ~ {Tame:1b,SaddleItem:{id:"saddle",Count:1b}}

2. Run the following command and start moving forward directly afterwards

   /kill @e[type=horse,limit=1,sort=nearest]