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, 2 insertions, 6 deletions

diff --git a/Lib/test/test_pkgimport.py b/Lib/test/test_pkgimport.py
index 370b2aa..5d9a451 100644
--- a/Lib/test/test_pkgimport.py
+++ b/Lib/test/test_pkgimport.py
@@ -7,7 +7,7 @@ import tempfile
 import unittest
 
 from importlib.util import cache_from_source
-from test.support import run_unittest, create_empty_file
+from test.support import create_empty_file
 
 class TestImport(unittest.TestCase):
 
@@ -76,9 +76,5 @@ class TestImport(unittest.TestCase):
         self.assertEqual(getattr(module, var), 1)
 
 
-def test_main():
-    run_unittest(TestImport)
-
-
 if __name__ == "__main__":
-    test_main()
+    unittest.main()