Breaking change: Y2038 support for .NET Arm32

[richlander]

We are making a major change to our Linux Arm32 support that affects all .NET versions.

• .NET 9 will only support Y2038-compatible Linux Arm32 distros, like Ubuntu 24.04 and (we expect) Debian 13.
• .NET 8 will remain Y2038 incompatible on Linux Arm32. Same applies to earlier .NET versions.

dotnet/core#9285

[Ellerbach]

[Triage] We discussed this specific topic and agree with the outcome pointed in the link.