[Libraries][iOS/MacCatalyst/tvOS] IsIanaIdTest fails from mismatched expectation #58440
Description
In #57732, several TimeZoneInfoTests were tweaked to pass on iOS/MacCatalyst/tvOS. At the time, when running tests, America/Buenos_Aires was no recognized as an IanaID on iOS/MacCatalyst/tvOS, so that value was used instead of Pacific Standard Time which throws TimeZoneNotFound ahead of returning false for IsIanaId.
I'm not certain what is supposed to be a TimeZoneId and not IanaId on iOS/MacCatalyst/tvOS yet, and I'm not sure exactly what had changed between that change and the latest run on #57208 to cause it to no longer not be an IanaId.
The fix should simply be finding a known TimeZoneId on iOS/MacCatalyst/tvOS that is and will not be recognized as an IanaId.
From another glance with #58440 (comment), it appears that the failure is directly from this addition to the test
The newest check fails on iOS/MacCatalyst/tvOS as the TimeZoneInfo.Local.Id is America/New_York. The check expects for the TimeZoneInfo.Local.Id to be an Iana Id if the platform is NOT windows or if the Id is NOT UTC. It seems as though America/New_York is evaluated as not being an Iana Id.