`RuntimeSdkImageTests.VerifyImagesWithWebApps` test is failing in PR validation on `sdk:4.8-windowsservercore-ltsc2016` image

WindowsLtsc2016_amd64 4.8-windowsservercore-ltsc2016-runtime tests are failing consistently in PR validation. This isn't happening in the internal CI.

Link to failing PR validation run: https://dev.azure.com/dnceng-public/public/_build/results?buildId=608811&view=logs&s=6884a131-87da-5381-61f3-d7acc3b91d76&j=b4a7524f-24ff-5cd3-3045-5ce9862a6c27

Test failure outputs (multiple across different tests):

System.InvalidOperationException : Failed to execute docker run --name webapp-133553521378571687 --rm  webapp-133553521378571687 powershell -command "dir ./bin/SimpleWebApplication.dll"
Exit code: 125
Standard Error: docker: Error response from daemon: container bed4570c99656a9e43c0f076450fcc1a9fd9826b45eb85f3a5e569fe1a61da74 encountered an error during hcsshim::System::Start: failure in a Windows system call: This operation returned because the timeout period expired. (0x5b4).

System.InvalidOperationException : Failed to execute docker build -t webapp-133553523877594066 --build-arg BASE_BUILD_IMAGE=mcr.microsoft.com/dotnet/framework/sdk:4.8-windowsservercore-ltsc2016 -f D:\a_work\1\a\bin\Microsoft.DotNet.Framework.Docker.Tests\release\projects\webapp-4.8\Dockerfile D:\a_work\1\a\bin\Microsoft.DotNet.Framework.Docker.Tests\release\projects\webapp-4.8
Exit code: -1
Standard Error: The command 'powershell -Command $ErrorActionPreference = 'Stop'; $ProgressPreference = 'SilentlyContinue'; msbuild SimpleWebApplication.sln /p:Configuration=Release' returned a non-zero code: 4294967295: failed to shutdown container: container 51f610b096f674c819bd3642b8b8bd8b3dbb8f2f87c7843709dc939b3199096b encountered an error during hcsshim::System::Shutdown: failure in a Windows system call: The handle is invalid. (0x6)

Start with RuntimeSdkImageTests.VerifyImagesWithWebApps and the linked PR validation run for the sdk:4.8-windowsservercore-ltsc2016 image. Compare the failing PR validation behavior with internal CI, focusing on the reported hcsshim start and shutdown errors. Done means the affected web app image tests complete successfully in PR validation.