Add sentry-dotnet to list of SDKs that support propagateTraceparent

[jamescrosswell]

Summary

• Add sentry-dotnet to list of SDKs that support propagateTraceparent
• Add PropagateTraceparent option to sentry-dotnet docs of SentryOptions

Remarks

follow-up question: docs

In the docs we mention

The following SDKs support the propagateTraceparent option:
see https://docs.sentry.io/concepts/otlp/sentry-with-otel/

Should we list .NET there too?

Originally posted by @Flash0ver in #5217 (comment)

[linear-code]

NET-709