Replace Environment.OsVersion on Windows with RtlGetVersion

[ThadHouse]

Environment.OsVersion Lies, so we need to change it.

[sciencewhiz]

When you say it lies, do you mean reporting version 10 on windows 11, or is it more then that?

[ThadHouse]

It reports whatever application compatibility says. So if you have compatibility set to 8, it will report 8.

Additionally, you have to have a manifest for newer versions, otherwise I think it defaults to 8.1 even without any compatibility mode.

[sciencewhiz]

It looks like a lot of the problems were fixed with .net 5. https://learn.microsoft.com/en-us/dotnet/core/compatibility/core-libraries/5.0/environment-osversion-returns-correct-version

[ThadHouse]

They were fixed and then reverted in .NET 6 by the higher ups.

dotnet/runtime#85758