Core/Unit: don't clear low health aura states on death

- Confirmed with sniffs, healthless states aren't cleared
- Prevents some procs from happening

Closes #19754

(cherry picked from commit 05b42eef7e)

src/server/game/Entities/Unit/Unit.cpp

@@ -8726,8 +8726,6 @@ void Unit::setDeathState(DeathState s)
 
     if (s == JUST_DIED)
     {
-        ModifyAuraState(AURA_STATE_HEALTHLESS_20_PERCENT, false);
-        ModifyAuraState(AURA_STATE_HEALTHLESS_35_PERCENT, false);
         // remove aurastates allowing special moves
         ClearAllReactives();
         ClearDiminishings();