Updates for .NET November 2024 Servicing and .NET 9 GA

[lbussell]

See Tasks needed for .NET 9 GA (#5059)

[lbussell]

@NikolaMilosavljevic I gave it my best effort porting the internal testing changes to this branch (which is based off of main). I added you as a reviewer so you can double-check it. If we start testing internal builds against this branch, I think we would iron out any issues with the merge pretty quickly.

[jander-msft]

Please move the .NET Monitor latest tags to the 9.0 images e.g. https://github.com/dotnet/dotnet-docker/pull/6042/commits/1363a995fe42fe30b2179fe018f0865b95898d8d

[lbussell]

Rebased to pick up the following commits and keep the version changes as the last commits:

• Re-enable pre-build validation for internal servicing testing
• Update common Docker engineering infrastructure with latest - from https://github.com/dotnet/dotnet-docker/pull/5995

[lbussell]

Final internal validation run for .NET 9: https://dev.azure.com/dnceng/internal/_build/results?buildId=2580014&view=results (internal MSFT link)