Issue #21741: Update 147 test modules to use test discovery.

I have compared output between pre- and post-patch runs of these tests
to make sure there's nothing missing and nothing broken, on both
Windows and Linux.  The only differences I found were actually tests
that were previously *not* run.

1 files changed, 1 insertions, 4 deletions

diff --git a/Lib/test/test_codecencodings_cn.py b/Lib/test/test_codecencodings_cn.py
index 60e69eb..d0e3a15 100644
--- a/Lib/test/test_codecencodings_cn.py
+++ b/Lib/test/test_codecencodings_cn.py
@@ -83,8 +83,5 @@ class Test_HZ(multibytecodec_support.TestBase, unittest.TestCase):
         (b"ab~{\x79\x79\x41\x44~}cd", "replace", "ab\ufffd\ufffd\u804acd"),
     )
 
-def test_main():
-    support.run_unittest(__name__)
-
 if __name__ == "__main__":
-    test_main()
+    unittest.main()