test_threaded_import: Fix unittest.main spelling (GH-93114)

The-Compiler · web-flow · commit 19710145b496 · 2022-05-25T10:59:32.000+03:00
diff --git a/Lib/test/test_importlib/test_threaded_import.py b/Lib/test/test_importlib/test_threaded_import.py
@@ -272,4 +272,4 @@ def setUpModule():
 
 
 if __name__ == "__main__":
-    unittets.main()
+    unittest.main()
