HTTP/3 & QUIC support

[dhalucario]

Feature Request

Motivation

IETF published HTTP/3 to the RFC as RFC 9114 and it seems to become the new internet standard. Every major browser and a good bunch of major webservers support it already.

Besides that HTTP/3 runs a lot faster based on a benchmark I have seen. Also package loss isn't as devestating as it is on HTTP/2 which is very important for mobile users.

Proposal

Implement RFC 9114.

Alternatives

None. We could ignore it.

[dhalucario]

Related to: hyperium/hyper#1818

[davidpdrsn]

axum is generic over the underlying transport so once hyper supports h3 then so does axum. So I'm gonna close this issue since there is nothing for us to do here. See the hyper issue you linked.