Add Azure Linux 4 images in nightly branch

[richlander]

We will need these images later this year. We can get started with images in nightly.

Related:

• Add dotnet-runtime-deps package for Azure Linux 4 dotnet#6579

[lbussell]

[triage] We can do this for .NET 11 now (to ship with Preview 5).

[lbussell]

This is complete in #7209