Core/Objects: Replace separate x,y,z,o getters for stationary position with single Position

Port From (https://github.com/TrinityCore/TrinityCore/commit/de740f0e76f6ebd02fcdb93a7a86260fe595d10c)

Source/Game/Entities/SceneObject.cs

@@ -178,10 +178,7 @@ namespace Game.Entities
         public override ObjectGuid GetOwnerGUID() { return m_sceneObjectData.CreatedBy; }
         public override uint GetFaction() { return 0; }
 
-        public override float GetStationaryX() { return _stationaryPosition.GetPositionX(); }
-        public override float GetStationaryY() { return _stationaryPosition.GetPositionY(); }
-        public override float GetStationaryZ() { return _stationaryPosition.GetPositionZ(); }
-        public override float GetStationaryO() { return _stationaryPosition.GetOrientation(); }
+        public override Position GetStationaryPosition() { return _stationaryPosition; }
         void RelocateStationaryPosition(Position pos) { _stationaryPosition.Relocate(pos); }
 
         public void SetCreatedBySpellCast(ObjectGuid castId) { _createdBySpellCast = castId; }