Added async, throwable support and unit tests

[nicofrancken]

I created separate Mock variants for the different cases async, throwable and async+throwable.

[frugoman]

This looks pretty good! Can you rebase from main and rename the new mocks to be [Name]Mock?

Someone else already contributed a ThrowingMock! please reuse that one instead if you can, adding to it's features if needed!

[sisoje]

there is a problem when using @escaping closure as param maybe you can ass to your code fix for that @nicofrancken