Update testtypes.py

Author: clintaire

mypy/test/testtypes.py

@@ -867,7 +867,7 @@ def test_generics_contravariant(self) -> None:
     def test_generics_with_multiple_args(self) -> None:
         self.assert_join(self.fx_co.hab, self.fx_co.hab, self.fx_co.hab)
         self.assert_join(self.fx_co.hab, self.fx_co.hbb, self.fx_co.hab)
-        self.assert_join(self.fx_co.had, self.fx_co.has, self.fx_co.hao)
+        self.assert_join(self.fx_co.had, self.fx_co.haa, self.fx_co.hao)
 
     def test_generics_with_inheritance(self) -> None:
         self.assert_join(self.fx_co.gsab, self.fx_co.gb, self.fx_co.gb)