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, 3 insertions, 4 deletions

diff --git a/Lib/test/test_wait3.py b/Lib/test/test_wait3.py
index bb71481..eb51b2c 100644
--- a/Lib/test/test_wait3.py
+++ b/Lib/test/test_wait3.py
@@ -5,7 +5,7 @@ import os
 import time
 import unittest
 from test.fork_wait import ForkWait
-from test.support import run_unittest, reap_children
+from test.support import reap_children
 
 if not hasattr(os, 'fork'):
     raise unittest.SkipTest("os.fork not defined")
@@ -31,9 +31,8 @@ class Wait3Test(ForkWait):
         self.assertEqual(status, 0, "cause = %d, exit = %d" % (status&0xff, status>>8))
         self.assertTrue(rusage)
 
-def test_main():
-    run_unittest(Wait3Test)
+def tearDownModule():
     reap_children()
 
 if __name__ == "__main__":
-    test_main()
+    unittest.main()