https://github.com/go-fed/httpsig seems to be unmaintained.
Switch to github.com/42wim/httpsig which has removed deprecated crypto
and default sha256 signing for ssh rsa.
No impact for those that use ed25519 ssh certificates.
This is a breaking change for:
- gitea.com/gitea/tea (go-sdk) - I'll be sending a PR there too
- activitypub using deprecated crypto (is this actually used?)