[QUIC] Missing implementation for `LocalCertificateSelectionCallback`

[ManickaP]

microsoft/msquic#1249

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Issue Details

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microsoft/msquic#1249

Author:	ManickaP
Assignees:	-
Labels:	untriaged, area-System.Net.Quic
Milestone:	-

[karelz]

Triage: This was broken on Linux prior to 7.0 for SslStream (we called the callback prior to handshake without info about trusted certs from server), we fixed it in 7.0. On Windows we didn't pass server certificate even on Windows prior to 7.0.
It is not recommended practice as it leaks some server info pontetially.

As a result we will call the callback before handshake via msquic (tracked by #70651) and wait for customers to ask for this feature (and work with msquic on that then).