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.

Lib/test/test_binascii.py

@@ -1,6 +1,5 @@
 """Test the binascii C module."""
 
-from test import support
 import unittest
 import binascii
 import array
@@ -262,11 +261,5 @@ class MemoryviewBinASCIITest(BinASCIITest):
     type2test = memoryview
 
 
-def test_main():
-    support.run_unittest(BinASCIITest,
-                         ArrayBinASCIITest,
-                         BytearrayBinASCIITest,
-                         MemoryviewBinASCIITest)
-
 if __name__ == "__main__":
-    test_main()
+    unittest.main()