Replace mocked_function.called_with() with mocked_function.assert_called_with()

Before mock v5, if you mock something, you can call any random function on it, and it just does nothing.

A common mistake is thus, to call mocked_function.called_with(param), it should have been:
mocked_function.assert_called_with(param)

It doesn't error, as it just makes a mock call to 'called_with' but it doesn't actually test the assertion.

In mock v5 from pypi they added some code to catch that common mistake and error out.

Thank you to Trent Lloyd for the above details and pointing this out.