mock: mock.Anything still works backwards

Description

This is very meta, and is probably a wontfix, but I feel like documenting it.

Step To Reproduce

func TestIfy(t *testing.T) {
	m := mock.Mock{}
	m.On("Do", "stuff").Return()
	m.MethodCalled("Do", mock.Anything)
}

Expected behavior

Test to fail. While "stuff" is anything, anything is not "stuff".

Actual behavior

Passes