Test with 5.1

[Sudha247]

It's been a while since we've run these benchmarks. It will be useful to run these with the latest Eio on OCaml 5.1. 5.1.0~rc3 is out at the time of writing this.

[craff]

I did, cohttpd-eio works. httpaf-eio fails to compile because result is not available and after added RUN opam install result and updating submodule, I still have

File "vendor/httpaf/eio/httpaf_eio.mli", line 45, characters 24-40:
45 |     -> (sw:Switch.t -> #Eio.Flow.two_way -> Eio.Net.Sockaddr.stream -> unit)
                             ^^^^^^^^^^^^^^^^
Error: Unbound class type Eio.Flow.two_way