add log

Author: MaxWang-MS

Assets/MRTK/Core/Utilities/Async/Internal/AsyncCoroutineRunner.cs

@@ -125,6 +125,7 @@ private void Update()
         {
             if (Instance != this)
             {
+                Debug.Log("[AsyncCoroutineRunner] Multiple active AsyncCoroutineRunners is present in the scene. Disabling duplicate ones.");
                 enabled = false;
                 return;
             }