Adds a basic sscan

[robertmarney]

This is imperfect as we are not implementing the actual scan options, however for the purposes of mocking it should be sufficient for most uses cases.

This allows the use of tagged collections in Laravel ^8.76

[thirsch]

Any update @robertmarney? We are facing the same issue since we've upgraded from Laravel 6 to 9 a couple of days ago.

[omansour]

see #107 seems better