DB/Gameobject: Deeprun Chest

Closes #12430
DB/Quest: Let Them Not Rise

By dr-j, closes #12484
Core/InstanceScript: Fix possible crash

Store Boos doors as GUID instead of GameObject* to avoid having pointers to free'd memory.
Core/InstanceScript: Fix possible crash

Store Boss doors/minions as GUID instead of GameObject*/Creature* to avoid accessing pointers to free'd memory.

Conflicts:
	src/server/game/Instances/InstanceScript.h