The Bug:

"minecraft.custom:minecraft.damage_dealt" doesn't increase when the thorns enchantment damages entities.

Steps to Reproduce:

1. Create a scoreboard objective for tracking when you deal damage and set it to display on the sidebar by using the commands provided below.  

   /scoreboard objectives add DamageDealt minecraft.custom:minecraft.damage_dealt

   /scoreboard objectives setdisplay sidebar DamageDealt

2. Summon a husk, attack it and take note of how the scoreboard increases.
3. Equip some armor enchanted with thorns by using the command provided below.

   /item replace entity @s armor.chest with minecraft:diamond_chestplate{Enchantments:[{id:"minecraft:thorns",lvl:3}]}

4. Switch into survival mode and allow the husk to damage you.
5. Wait for the thorns enchantment to damage the husk.
6. Take note as to whether or not "minecraft.custom:minecraft.damage_dealt" increases when the thorns enchantment damages entities.

Observed Behavior:

"minecraft.custom:minecraft.damage_dealt" doesn't increase when the thorns enchantment damages entities.

Expected Behavior:

"minecraft.custom:minecraft.damage_dealt" would increase when the thorns enchantment damages entities.