[Demon Hunter] Fix Doomsayer trigger asymmetric buff expiration

[taherbert]

Summary

The doomsayer_trigger_t guard checks both doomsayer_in_combat and doomsayer_out_of_combat buffs (line 3161), but only expires doomsayer_in_combat (line 3172). If the out-of-combat buff were the active one when the trigger fires, it would not be consumed — allowing a double trigger on the next melee attack.

Fix

Expire both buffs unconditionally after the trigger fires. buff_t::expire() is a no-op on inactive buffs, so both calls are always safe.

BASE::p()->buff.doomsayer_in_combat->expire();
BASE::p()->buff.doomsayer_out_of_combat->expire();

In practice, the combat state callback (lines 9742-9753) normally swaps to doomsayer_in_combat before the first attack, so this is a latent correctness fix rather than a commonly triggered bug.