Unify certificate chain building between `SslStream` and `WinHttpHandler`

[ManickaP]

There are two different source files doing similar thing for certificate chain building on Windows:

• WinHttpCertificateHelper.cs
• CertificateValidation.Windows.cs

The WinHttpHandler should be replaced with the one from SslStream to unify the logic, remove duplicates and make the future maintenance simpler.

cc @rzikm

[dotnet-policy-service]

Tagging subscribers to this area: @dotnet/ncl
See info in area-owners.md if you want to be subscribed.

[dotnet-policy-service]

Tagging subscribers to this area: @dotnet/ncl, @bartonjs, @vcsjones
See info in area-owners.md if you want to be subscribed.

[wfurt]

do we do something similar for Quic? If so I would add to the pack.

[ManickaP]

It uses the same one as SslStream, the one from the second bullet point.