Unwrap win32 data object

src/Windows/Avalonia.Win32/DataObject.cs

@@ -103,6 +103,7 @@ namespace Avalonia.Win32
 
 
         private IDataObject _wrapped;
+        public IDataObject Wrapped => _wrapped;
 
         public DataObject(IDataObject wrapped)
         {

src/Windows/Avalonia.Win32/OleDropTarget.cs

@@ -217,7 +217,7 @@ namespace Avalonia.Win32
 
             if (MicroComRuntime.TryUnwrapManagedObject(pDataObj) is DataObject dataObject)
             {
-                return dataObject;
+                return dataObject.Wrapped;
             }
             return new OleDataObject(pDataObj);
         }