test: Fix tests

Author: Xiaokang2022

Lib/test/test_ttk/test_widgets.py

@@ -125,7 +125,6 @@ def test_cb(arg1, **kw):
 
     def test_widget_cget(self):
         # Check whether the return value of cget is a string
-        self.assertIsInstance(self.widget.cget("width"), str)
         self.assertEqual(self.widget.cget("state"), tkinter.NORMAL)
         self.assertEqual(self.widget.cget("text"), "Text")