Issue #19586: Update remaining deprecated assertions to their preferred usage.

tests/test_upload.py

@@ -114,11 +114,11 @@ class uploadTestCase(PyPIRCCommandTestCase):
          # what did we send ?
         headers = dict(self.last_open.req.headers)
         self.assertEqual(headers['Content-length'], '2087')
-        self.assert_(headers['Content-type'].startswith('multipart/form-data'))
+        self.assertTrue(headers['Content-type'].startswith('multipart/form-data'))
         self.assertEqual(self.last_open.req.get_method(), 'POST')
         expected_url = 'https://pypi.python.org/pypi'
         self.assertEqual(self.last_open.req.get_full_url(), expected_url)
-        self.assert_(b'xxx' in self.last_open.req.data)
+        self.assertTrue(b'xxx' in self.last_open.req.data)
 
 def test_suite():
     return unittest.makeSuite(uploadTestCase)