Adding HttpWebRequest to HttpClient Migration Guide

[liveans]

Summary

Fixes dotnet/runtime#92690

/cc @dotnet/ncl

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Internal previews

📄 File	🔗 Preview link
docs/fundamentals/networking/http/httpclient-migrate-from-httpwebrequest.md	docs/fundamentals/networking/http/httpclient-migrate-from-httpwebrequest

[rzikm]

looks good so far, do you plan to add more complex examples showcasing how to migrate use of certificates or ConnectCallback?

[liveans]

looks good so far, do you plan to add more complex examples showcasing how to migrate use of certificates or ConnectCallback?

Yes, this is ongoing work and this is on my todo list, and I'll actually add specific links to those sections in Notes section in the table.

[ManickaP]

I like the examples for specific scenarios, it's very practical. I also like the quick reference tables with the mapping.
Overall, I like the direction here, keep going!

I left some comments, mostly about sample code. I think we should be very careful with the code as people will copy-paste this as-is.

[MihaZupan]

Thank you for working on this, it'll be nice to have a common place we can link people to

[MihaZupan]

Thank you for working on this.

(don't get scared by the number of comments, it's mainly small tweaks in example code)

[liveans]

@dotnet/docs gentle reminder on this PR, can you take a look or I can merge this as-is and can create a follow-up PR for reviews.