HTTP/3: Test alt-svc upgrade from HTTP/1.1 and HTTP/2 to HTTP/3

[JamesNK]

Currently blocked from being added to #34104

Blocked because HTTP/1.1 and HTTP/2 require suppression of cert error using callback, and HTTP/3 errors when there is a callback.

See dotnet/runtime#55193 and dotnet/runtime#55192

[ghost]

Thanks for contacting us.

We're moving this issue to the Next sprint planning milestone for future evaluation / consideration. We would like to keep this around to collect more feedback, which can help us with prioritizing this work. We will re-evaluate this issue, during our next planning meeting(s).
If we later determine, that the issue has no community involvement, or it's very rare and low-impact issue, we will close it - so that the team can focus on more important and high impact issues.
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