Replace Butterfly with SkyWalking

[aioloswong]

Expected Behavior / New Feature

As butterfly is no longer being maintained，please replace it with apache skywalking.
https://github.com/SkyAPM/SkyAPM-dotnet
https://github.com/apache/skywalking

[raman-m]

Will you personally contribute to release a Tracing provider NuGet package for Ocelot?

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https://github.com/SkyAPM/SkyAPM-dotnet

Releases → v2.1.0-release is the latest one on Sep 27, 2022
So, this repo is not supported also ⚠️

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https://github.com/apache/skywalking

But this is Java product! Some drivers?
I've checked SkyWalking docs and there is no .NET agent at all! See: Agents

[raman-m]

@RaynaldM @ggnaegi This is Tracer and monitoring product

https://github.com/apache/skywalking
Apache SkyWalking is amazing product! It is coded in Java! So, an agent lib is required, but there is no .NET agent 😢