Unity 获取预制件嵌套的子预制件的路径

```csharp
 public static string GetPrefabAssetPath(GameObject go)
 {
     if (PrefabUtility.IsAnyPrefabInstanceRoot(go))
     {
         return PrefabUtility.GetPrefabAssetPathOfNearestInstanceRoot(go);
     }
     return null;
 }