Enchantments with 0 anvil cost still increase their anvil cost via the enchantment's level

When creating a custom enchantment, the object for anvil cost accepts a 0.

Unsurprisingly it defaults to a base cost of 1 in-game. However, if the enchantment is trying to be applied at a higher level, the anvil cost multiplies the generated default cost by the enchantment level, instead of defaulting to 1. This results in a level 5 enchantment, with anvil cost 0, actually costing 5 levels on the anvil.

Either the anvil cost object in enchantment jsons need to have a minimum expected value of 1 to better communicate this (and throw an error in the console if not); or more ideally, the anvil should calculate the cost of applying the enchantment, including the multiplying by enchantment level, and only default to 1 if the final calculated value is less than 1 (nicknaming adding 1 level cost regardless of operation should still occur regardless).

Steps to Reproduce:

• Generate a world with the datapack included in a comment (contains an enchantment with anvil cost 0, applicable to a stick).

• Grab a stick item and an enchanted book with the anvil cost 0 enchantment at level 1, and observe the 1 level cost when placed properly on an anvil.

• Now replace the enchanted book with a book with the same enchantment but at a higher level of 2-5, and observe the level cost of it on the anvil.

Expected Results:

• The anvil cost would default to 1 for higher enchantment levels (with attempting to add a nickname increasing it to 2).

Observed Results:

• The anvil cost increases to higher than 1, scaling with the level of the applying enchantment. So the anvil cost 0 enchantment at level 2 is an anvil cost of 2, level 3 is an anvil cost of 3, and so on.