Core/Units: Calculate HoverHeight from model data

Port From (https://github.com/TrinityCore/TrinityCore/commit/d6133c78de9e2272765c2cfda82c440663acd254)

Source/Game/Entities/Player/Player.DB.cs

@@ -2918,7 +2918,6 @@ namespace Game.Entities
             }
 
             SetObjectScale(1.0f);
-            SetHoverHeight(1.0f);
 
             // load achievements before anything else to prevent multiple gains for the same achievement/criteria on every loading (as loading does call UpdateAchievementCriteria)
             m_achievementSys.LoadFromDB(holder.GetResult(PlayerLoginQueryLoad.Achievements), holder.GetResult(PlayerLoginQueryLoad.CriteriaProgress));

Source/Game/Entities/Player/Player.cs

@@ -228,7 +228,6 @@ namespace Game.Entities
             }
 
             SetUnitFlag2(UnitFlags2.RegeneratePower);
-            SetHoverHeight(1.0f);            // default for players in 3.0.3
 
             SetWatchedFactionIndex(0xFFFFFFFF);