Remove duplicated tests in test_base64 (gh-125346) (GH-141153)

Author: serhiy-storchaka

Lib/test/test_base64.py

@@ -394,10 +394,6 @@ def test_b32decode_casefold(self):
         self.assertRaises(binascii.Error, base64.b32decode, b'me======')
         self.assertRaises(binascii.Error, base64.b32decode, 'me======')
 
-        # Mapping zero and one
-        eq(base64.b32decode(b'MLO23456'), b'b\xdd\xad\xf3\xbe')
-        eq(base64.b32decode('MLO23456'), b'b\xdd\xad\xf3\xbe')
-
     def test_b32decode_map01(self):
         # Mapping zero and one
         eq = self.assertEqual