Core/Battlegrounds: Replace manual criteria timer starts in battlegrounds with new GameEvents api

Port From (https://github.com/TrinityCore/TrinityCore/commit/111fc6ac6fd703bb645046e7a477a986d8519a64)

Source/Game/BattleGrounds/Zones/ArathiBasin.cs

@@ -216,7 +216,7 @@ namespace Game.BattleGrounds.Zones
             DoorOpen(ABObjectTypes.GateH);
 
             // Achievement: Let's Get This Done
-            StartCriteriaTimer(CriteriaStartEvent.SendEvent, EventStartBattle);
+            TriggerGameEvent(EventStartBattle);
         }
 
         public override void AddPlayer(Player player)

Source/Game/BattleGrounds/Zones/EyeofStorm.cs

@@ -131,7 +131,7 @@ namespace Game.BattleGrounds.Zones
             }
 
             // Achievement: Flurry
-            StartCriteriaTimer(CriteriaStartEvent.SendEvent, EotSMisc.EventStartBattle);
+            TriggerGameEvent(EotSMisc.EventStartBattle);
         }
 
         void AddPoints(Team Team, uint Points)

Source/Game/BattleGrounds/Zones/StrandofAncients.cs

@@ -343,7 +343,7 @@ namespace Game.BattleGrounds.Zones
                     ToggleTimer();
                     DemolisherStartState(false);
                     Status = SAStatus.RoundOne;
-                    StartCriteriaTimer(CriteriaStartEvent.SendEvent, (Attackers == TeamId.Alliance) ? 23748 : 21702u);
+                    TriggerGameEvent(Attackers == TeamId.Alliance ? 23748 : 21702u);
                 }
                 if (TotalTime >= SATimers.BoatStart)
                     StartShips();
@@ -366,7 +366,7 @@ namespace Game.BattleGrounds.Zones
                     ToggleTimer();
                     DemolisherStartState(false);
                     Status = SAStatus.RoundTwo;
-                    StartCriteriaTimer(CriteriaStartEvent.SendEvent, (Attackers == TeamId.Alliance) ? 23748 : 21702u);
+                    TriggerGameEvent(Attackers == TeamId.Alliance ? 23748 : 21702u);
                     // status was set to STATUS_WAIT_JOIN manually for Preparation, set it back now
                     SetStatus(BattlegroundStatus.InProgress);
                     foreach (var pair in GetPlayers())

Source/Game/BattleGrounds/Zones/WarsongGluch.cs

@@ -193,7 +193,7 @@ namespace Game.BattleGrounds.Zones
             SpawnBGObject(WSGObjectTypes.DoorH4, BattlegroundConst.RespawnOneDay);
 
             // players joining later are not eligibles
-            StartCriteriaTimer(CriteriaStartEvent.SendEvent, 8563);
+            TriggerGameEvent( 8563);
         }
 
         public override void AddPlayer(Player player)