Rotation and origin tags in mobs.json are being ignored

Version - 1.2.0

Summary:
When the model of an entity is modified, it ignores the rotation and origin stated if the original geometry has an animation. Therefore when modifying geometries like the saddle, legs or head it will default to the vanilla rotation and origin.

Impact: This prevents the use of rotation in models on a large portion of geometries. In the case of the spider this prevents/limits the use of any custom rotation in the model on all geometries apart from the body.

Repro Steps:
1. Load the resource pack attached to this report
2. Spawn a spider

Observed Results:
The geometry appears but ignores the rotation and origin stated in the json. In this case it lacks the rotation. Instead it forces the vanilla positions because of the animations.

Expected Results:
The rotation and origin tags override the vanilla values, thus displaying what is written in the json.

Screenshots/Videos attached: Yes