fix: dereferenced pointer

Author: lucafolloni

src/server/scripts/Spells/spell_dk.cpp

@@ -155,7 +155,7 @@ class spell_dk_raise_ally : public SpellScript
         if (!targetGuid)
             return SPELL_FAILED_BAD_TARGETS;
 
-        Unit *target = ObjectAccessor::GetUnit(GetSpell()->GetCaster(), targetGuid);
+        Unit *target = ObjectAccessor::GetUnit(*(GetSpell()->GetCaster()), targetGuid);
         Player *unitTarget = target ? target->ToPlayer() : nullptr;
         if (!unitTarget)
             return SPELL_FAILED_BAD_TARGETS;