changed typecheck for list value to use isinstance instead of type

Author: kenshima4

dash/dash.py

@@ -719,6 +719,9 @@ def _layout_value(self):
 
     @layout.setter
     def layout(self, value):
+        if isinstance(value, list):
+            value = html.Div(value)
+
         _validate.validate_layout_type(value)
         self._layout_is_function = callable(value)
         self._layout = value