Enable SourceLink for .NET projects

[weshaggard]

See https://github.com/dotnet/SourceLink for how to enable SourceLink. This will give us the ability to debug through the source code of our libraries as well as it will add some additional metadata to the information version that points to the sha of the source when it was built.

[weshaggard]

@tmat Do we still need to reference the SourceLink package or if we are using the .NET Core 3 SDK is the support built in?

[tmat]

Yes, there is no plan to include SourceLink in the SDK.

[weshaggard]

@chidozieononiwu looks like there are some projects that already reference SourceLink (https://github.com/Azure/azure-sdk-for-net/search?q=sourcelink&unscoped_q=sourcelink) which is why @mitchdenny said it worked for some he tried already. Please move that package reference to the common targets file and update the version to the latest published on nuget.org.

[SeanFeldman]

It was extremely convenient to step into the code w/o the need to set up symbols server.
I'd like to ask what was the reason SourceLink was disqualified?

[weshaggard]

We have enabled SourceLink for all our data-plane packages by default, see PR #6867. If you are seeing something not working please let us know.