Fix nativeaot outerloop

[MichalStrehovsky]

typeof(RegionInfo).Assembly.GetType is too difficult to analyze for trimming. Native AOT outerloop runs crash with a NullReferenceException because the property is not reflection-visible.

[MichalStrehovsky]

/azp run runtime-nativeaot-outerloop

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[MichalStrehovsky]

@carlossanlop this test was backported to both .NET 8 and .NET 9 and has been failing in outerloops ever since. We're about to ship .NET 9 GA with 16 out of 20 runtime-nativeaot-outerloop jobs consistently failing. I assume this means they are not part of our shipping criteria. Do you know how would I go about proposing adding runtime-nativeaot-outerloop to the shipping criteria?

Cc @dotnet/ilc-contrib

[MichalStrehovsky]

This doesn't fix all of outerloop because people were being productive writing more trim-unfriendly test code. I'll fix in a follow up in case we need to backport this PR.

[MichalStrehovsky]

/backport to release/9.0

[github-actions]

Started backporting to release/9.0: https://github.com/dotnet/runtime/actions/runs/11399867413

[MichalStrehovsky]

/backport to release/8.0

[github-actions]

Started backporting to release/8.0: https://github.com/dotnet/runtime/actions/runs/11399872244