fix netrc unit tests

Co-authored-by: 🇺🇦 Sviatoslav Sydorenko (Святослав Сидоренко) <[email protected]>

Lib/test/test_netrc.py

@@ -1,9 +1,5 @@
-import netrc
-import os
-import sys
-import textwrap
-import unittest
-from test.support import os_helper, run_unittest
+import netrc, os, unittest, sys, textwrap
+from test.support import os_helper
 
 try:
     import pwd
@@ -12,7 +8,6 @@
 
 temp_filename = os_helper.TESTFN
 
-
 class NetrcTestCase(unittest.TestCase):
 
     def make_nrc(self, test_data):
@@ -329,9 +324,5 @@ def test_security(self):
                              ('anonymous', '', 'pass'))
 
 
-def test_main():
-    run_unittest(NetrcTestCase)
-
-
 if __name__ == "__main__":
     unittest.main()