One more adjustment for Python 3.9a2

Author: nedbat

tests/test_execfile.py

@@ -46,7 +46,7 @@ def test_run_python_file(self):
         self.assertEqual(mod_globs['__main__.DATA'], "xyzzy")
 
         # Argv should have the proper values.
-        self.assertEqual(mod_globs['argv0'], python_reported_file(TRY_EXECFILE))
+        self.assertEqual(mod_globs['argv0'], TRY_EXECFILE)
         self.assertEqual(mod_globs['argv1-n'], ["arg1", "arg2"])
 
         # __builtins__ should have the right values, like open().