This is a deterministic version of Minica, which is useful for generating certificates in NixOS tests.
Currently this is implemented by patching Go in order to introduce determinism
in randutil.MaybeReadByte and also uses sed to patch Minica.
The implementation is gruesome and will probably break with future versions of Minica. This is deliberate so that I someday™ get annoyed enough to implement it in sane way as an upstream pull request.