When the "Villager Trade Rebalance" experiment is enabled, apprentice armorers sell iron helmets instead of iron leggings or chestplates

The trades for non-jungle/swamp apprentice armorers selling iron leggings and chestplates are incorrectly defined to sell iron helmets instead.

Pictured: Trade #3 is supposed to be 7 emeralds for iron leggings, Trade #4 is supposed to be 9 emeralds for iron chestplate.