CLN: Remove a test case about Timestamp to TestTimestamp (#13722)

Author: yui-knk

pandas/tseries/tests/test_timedeltas.py

@@ -188,7 +188,6 @@ def test_construction(self):
         self.assertEqual(Timedelta('').value, iNaT)
         self.assertEqual(Timedelta('nat').value, iNaT)
         self.assertEqual(Timedelta('NAT').value, iNaT)
-        self.assertTrue(isnull(Timestamp('nat')))
         self.assertTrue(isnull(Timedelta('nat')))
 
         # offset

pandas/tseries/tests/test_timeseries.py

@@ -4389,6 +4389,8 @@ def check(val, unit=None, h=1, s=1, us=0):
         result = Timestamp('NaT')
         self.assertIs(result, NaT)
 
+        self.assertTrue(isnull(Timestamp('nat')))
+
     def test_roundtrip(self):
 
         # test value to string and back conversions