Changing the mob type of an ominous trial spawner with a spawn egg causes spawned mobs to wear armor irrespective of the mob type

When changing a mob in an ominous spawner using a spawn egg, it results in the new mob spawning, however it will be wearing armor, even if this mob cannot normally wear armor through any other method.

 

Expected Behavior: Armor would be tied to the mob type directly, as that is how normal spawners function.

Actual Behavior: Armor is added to mobs completely independent of what mob is set inside the spawner.