yocaml_unix: use digestif for SHA256 computation instead of cryptokit

[hannesm]

just a preference :)

[xvw]

Hi @xhtmlboi has some issue to connect on github (since they ask for a mobile :D, we currently drafting the new proposition for YOCaml here: https://gitlab.com/funkywork/yocaml, and we will move the new version from gitlab to here) but we agree with the patch. I do not know why he chose Cryptokit on the first attempt.

Could you please just add an entry in https://github.com/xhtmlboi/yocaml/blob/main/CHANGES.md (in a section **dev (unreleased) with a subsection yocaml_unix)?

Thanks a lot.

[hannesm]

sure, done in d36972c

[xvw]

Thanks, I'll merge after the pipeline!
@dinosaure should we make a new release (or you are using a custom opam repo?)

[dinosaure]

@dinosaure should we make a new release (or you are using a custom opam repo?)

I see some activities on your side (on https://gitlab.com/funkywork/yocaml), we probably can wait for your work and do a big release then?