fix quest demon souls

[Username5173]

Changes proposed:

• If you use the quest item the npc spawns, gives credit for the killed demons and despawns their corpses

Issues addressed: Closes # (insert issue tracker number) fixes the quest demon souls https://www.wowhead.com/quest=37653/demon-souls

Tests performed: (Does it build, tested in-game, etc.) tested ingame

Known issues and TODO list: (add/remove lines as needed)

• On retail the npc uses a spell on the npcs instead of making them despawn

[Username5173]

Do you still have the sniffs from azsuna?