.NET OTEL/Activity SpanLinks Setup & Configuration

[link04]

Motivation

To test the SpanLinks implementation merged in DataDog/dd-trace-dotnet#5627 after being able to pass them locally.

Changes

Updates the .NET service OTEL parametric class to check for the links in the incoming request and try to add them like a user would using the ActivityLink class which the .NET tracer now is able to duck cast and add to its spans.

Workflow

1. ⚠️ Create your PR as draft ⚠️
2. Work on you PR until the CI passes (if something not related to your task is failing, you can ignore it)
3. Mark it as ready for review
   • Test logic is modified? -> Get a review from RFC owner. We're working on refining the codeowners file quickly.
   • Framework is modified, or non obvious usage of it -> get a review from R&P team

🚀 Once your PR is reviewed, you can merge it!

🛟 #apm-shared-testing 🛟

Reviewer checklist

• Relevant label (run-parametric-scenario, run-profiling-scenario...) are presents
• If PR title starts with [<language>], double-check that only <language> is impacted by the change
• No system-tests internal is modified. Otherwise, I have the approval from R&P team
• CI is green, or failing jobs are not related to this change (and you are 100% sure about this statement)
• A docker base image is modified?
  • the relevant build-XXX-image label is present
• A scenario is added (or removed)?
  • Get a review from R&P team

[zacharycmontoya]

LGTM!