Core/Auras: Implement SpellAuraInterruptFlags2::DuelEnd

Port From (https://github.com/TrinityCore/TrinityCore/commit/ca66da1c97acaff18b318b3e856d54127cb96a6b)

Source/Game/Entities/Player/Player.Combat.cs

@@ -514,6 +514,9 @@ namespace Game.Entities
                     RemoveAura(pair);
             }
 
+            RemoveAurasWithInterruptFlags(SpellAuraInterruptFlags2.DuelEnd);
+            opponent.RemoveAurasWithInterruptFlags(SpellAuraInterruptFlags2.DuelEnd);
+
             // cleanup combo points
             ClearComboPoints();
             opponent.ClearComboPoints();