Update various test modules to use unittest.main() for test discovery
instead of manually listing tests for test.support.run_unittest().
diff --git a/Lib/test/test_sched.py b/Lib/test/test_sched.py
index 1fe6ad4..853b4d8 100644
--- a/Lib/test/test_sched.py
+++ b/Lib/test/test_sched.py
@@ -197,8 +197,5 @@
         self.assertEqual(l, [])
 
 
-def test_main():
-    support.run_unittest(TestCase)
-
 if __name__ == "__main__":
-    test_main()
+    unittest.main()