Attributes on Latest Dev build apply to all Slots on 1.20.4

Title. With this item, where attributes are defined in MainHand, attributes instead apply to all slots.

test-item1:
  Id: IRON_SWORD
  Display: 'Sword of Testing'
  Attributes:
    MainHand:
      Damage: 12
      AttackSpeed: -2.4 ADD

Attributes should only apply to the defined slots.