Added Action for sending Game Manager default Events (Used for Editor fixes)

Runtime/LevelScripting/Actions/GameManagerSendStartupMessageAction.cs

+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+
+namespace GameplayIngredients.Actions
+{
+    public class GameManagerSendStartupMessageAction : ActionBase
+    {
+        public enum MessageType
+        {
+            MainMenuStart,
+            GameLevelStart,
+        }
+
+        public MessageType messageType;
+
+        public override void Execute(GameObject instigator = null)
+        {
+            switch(messageType)
+            {
+                case MessageType.GameLevelStart:
+                    Messager.Send(GameManager.GameLevelStartMessage);
+                    break;
+                case MessageType.MainMenuStart:
+                    Messager.Send(GameManager.MainMenuStartMessage);
+                    break;
+            }
+        }
+    }
+}

Runtime/LevelScripting/Actions/GameManagerSendStartupMessageAction.cs.meta

+fileFormatVersion: 2
+guid: 15ae69d69e7aeaf4fbfb02e7175ed5f5
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {fileID: 2800000, guid: af9148c7de0fc6444b7e4e050f116dd0, type: 3}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: