[MC-137906] 物品属性不能叠加 Attributes don't stack

当持有/装备多个带有属性的物品时，属性不相互冲突的前提下，属性会优先选择最后装备的物品的属性，而无法叠加所有物品的属性。
When armor up equipments that have attribute nbts (do not conflict),only the last armored up works instead of adding all attributes up.
我只在玩家本身上做了这个实验，不清楚是否别的实体也无法叠加。
I only test this on players but not all mobs so it leaves unknown whether it works properly on other mobs.

give @p diamond_chestplate{Unbreakable:1,AttributeModifiers:[
{Slot:"chest",AttributeName:"generic.maxHealth",Name:"generic.maxHealth",Amount:12,Operation:0,UUIDLeast:1,UUIDMost:1}],HideFlags:63} 1

give @p diamond_helmet{Unbreakable:1,AttributeModifiers:[{Slot:"head",AttributeName:"generic.maxHealth",Name:"generic.maxHealth",Amount:8,Operation:0,UUIDLeast:1,UUIDMost:1}],HideFlags:63} 1