Add unit tests for how the rows in the TwoFAVC are computed

[mokagio]

Builds on top #809 . While looking at that PR, I noticed that there are three essentially boolean parameters that drive the rows behavior (either actual Bool or Optional .some vs .none). That results into eight possible runtime input configurations. Too many to test manually, but easily testable via unit tests.

In truth, there's an additional boolean parameter, #available(iOS 16) but I decided to ignore that under the assumption that it's most of the user base.

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• [x] I have considered if this change warrants release notes and have added them to the appropriate section in the CHANGELOG.md if necessary. — N.A.

[mokagio]

Thanks for indulging my silly typo fix!

Not at all silly! As you know, tpyos matter here. Ref pb6Nl-dHI-p2