feat: improve wording of Which and Satisfy

[vbreuss]

Improve Which/Should and Satisfy/To method by adding an intermediate result, so it now reads

await Expect.That(subject).Should().Be<Dummy>().Which(p => p.Value).Should(e => e.Be("bar"));
await Expect.That(subject).Should().Satisfy<Other, int>(o => o.Value).To(v => v.Be(2));