Improve how Azure DevOps extensions identifies interesting stack trace entries

[nohwnd]

Describe the bug

#5260 (comment)

The extension is now relying on MSTest to provide a filtered stack trace and just takes the first line.

This is not the desired state, we need to find the first entry that belongs to a code file in the repository, which gives us the best chance of reporting the error back to github PR (via the standard AzDo integration).

Look at how TFS DistributedLogger for msbuild does it, and possibly figure out better ways to provide the repository root. (e.g. if we move the run to a different server we won't be able to find the .git folder, so we need to provide it externally, or as a glob *MyProject/src.

Steps To Reproduce

Use the extension with xunit and see it fail to report the error back to GH (most likely).

[nohwnd]

pointing at the first method in the repo is also not universal solution, if we throw from helper method we will end up with all exceptions pointing to that helper method, instead of to the test. It would be better for a method to be able to opt out from the stack trace.

Like here:

Where 20 more errors follow, because tests use this helper class.

[Youssef1313]

https://learn.microsoft.com/en-us/dotnet/api/system.diagnostics.stacktracehiddenattribute?view=net-9.0 is already there for net6.0+.
Not available for .NET Framework though.

[nohwnd]

I did the described improvements, we find the first path that exists within the repository, unless that path ends with *Assert.cs, then we skip it and go to next, to avoid having helpers always show up.

We do get it from stack trace, so the attribute you mention is useful.

https://github.com/microsoft/testfx/blob/main/src/Platform/Microsoft.Testing.Extensions.AzureDevOpsReport/AzureDevOpsReporter.cs#L214

I think we can close this for now.