QUIC: revisit support for ServerCertificateContext

[wfurt]

#53175 added support for ServerCertificateContext. While it is functionally complete, it uses reflection to access private members of the ServerCertificateContext. This happens once per server so there may not be performance issue but it may become maintenance hassle.
We should look into new API so we can access everything directly. (or find some other solution)

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Issue Details

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#53175 added support for ServerCertificateContext. While it is functionally complete, it uses reflection to access private members of the ServerCertificateContext. This happens once per server so there may not be performance issue but it may become maintenance hassle.
We should look into new API so we can access everything directly. (or find some other solution)

Author:	wfurt
Assignees:	-
Labels:	area-System.Net.Quic
Milestone:	-

[karelz]

Triage: We should remove reflection in 7.0, so we will need the new APIs in SslStream.

[rzikm]

Proposal to make ServerCertificateContext properties public: #67552