Core/SAI: Fix creatures casting spells while moving with flag SMARTCAST_COMBAT_MOVE

Port From (https://github.com/TrinityCore/TrinityCore/commit/b3545479bfbd2b743288bd32094ce8c4856a1e3d)

Source/Game/AI/SmartScripts/SmartAI.cs

@@ -843,7 +843,7 @@ namespace Game.AI
             GetScript().ProcessEventsFor(SmartEvents.RewardQuest, player, quest.Id, opt);
         }
 
-        public void SetCombatMove(bool on)
+        public void SetCombatMove(bool on, bool stopMoving = false)
         {
             if (_canCombatMove == on)
                 return;
@@ -870,7 +870,11 @@ namespace Game.AI
                 {
                     var movement = me.GetMotionMaster().GetMovementGenerator(a => a.GetMovementGeneratorType() == MovementGeneratorType.Chase && a.Mode == MovementGeneratorMode.Default && a.Priority == MovementGeneratorPriority.Normal);
                     if (movement != null)
+                    {
                         me.GetMotionMaster().Remove(movement);
+                        if (stopMoving)
+                            me.StopMoving();
+                    }
                 }
             }
         }

Source/Game/AI/SmartScripts/SmartScript.cs

@@ -482,7 +482,7 @@ namespace Game.AI
                                         !_me.IsWithinLOSInMap(target) || !hasPower || _me.HasUnitFlag(UnitFlags.Silenced))
                                         allowMove = true;
 
-                                    ((SmartAI)_me.GetAI()).SetCombatMove(allowMove);
+                                    ((SmartAI)_me.GetAI()).SetCombatMove(allowMove, true);
                                 }
 
                                 _me.CastSpell(target.ToUnit(), e.Action.cast.spell, new CastSpellExtraArgs(triggerFlag));