Fix Linter Error

"result" was unused, and there was a type error in the test because we're explicitly trying to cause a failure due to invalid file.

Author: theGOTOguy

tests/test_main.py

@@ -24,7 +24,7 @@ def test_set_key_no_file(tmp_path):
 
 def test_set_key_invalid_file():
     with pytest.raises(TypeError):
-        result = dotenv.set_key(None, "foo", "bar")
+        dotenv.set_key(None, "foo", "bar")  # type: ignore
 
 
 @pytest.mark.parametrize(