[lua] [core] Chi Blast: fix xi.ability.adjustDamage param fix, rename xi.ability.adjustDamage params, add safety to UpdateEnmityFromDamage

[WinterSolstice8]

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What does this pull request do?

Apparently Chi Blast was adding the mob to it's own enmity list from damage instead of the player. This fixes that and adds safety so that can't happen again

Steps to test these changes

Chi Blast a mob, see !exec print(tostring(target:getEnmityList())) doesnt contain the mob itself