h2c upgrade is now deprecated (RFC 9113 Section 3.1)

[gquintard]

https://rfcinfo.com/rfc-9113/3-starting-http2/#31-http2-version-identification

I can prepare a PR to drop the test suite if you'd like

[MDA2AV]

Hi, the h2c profiles here are prior-knowledge only, h2load runs with -p h2c, and validation asserts via curl --http2-prior-knowledge that the negotiated version is 2.

There's never been an upgrade/h2-settings path in the harness, so §3.1 isn't an issue, what these exercise is §3.3, which is still normative and is the common backend/service-mesh pattern.

I agree we can make this tests unscored and eventually drop them to reduce the test suite size though. The reason why we even have h2c was a discussion in the past which led to us wanting to benchmark the TLS overhead in h2 plus it seems that h2c is still quite adopted by some grpc implementers, mainly in IoT applications

[gquintard]

ah, nevermind me then!