Replace clone with download

[alecandido]

It seems that to clone a repository from GitHub now you always need to set credentials, whatever URL you are using.

So, I'm proposing to replace repositories (that in general are also an overkill) with the master/main branch content, i.e. instead of cloning with Git we will just download the zip content of one branch from GitHub.
E.g. for this repository the corresponding URL is https://github.com/NNPDF/runcards/archive/refs/heads/master.zip

The other option is to use the latest release, e.g. for PineAPPL the URL to the zip of the last release can be found with a request to:
https://api.github.com/repos/n3pdf/pineappl/releases/latest
(the key in the response is actually zipball_url). Once we have the URL, one GET more and we'll have the zip as well (for tarball replace zip with tar in the key.

Which one do you prefer?

• master/main: always updated
• latest release: more stable

TODO:

• fix version
• replace repositories with tarballs
• Support config files pinecards#127 (comment)
• purge unused (and thus unmaintained) Git related code
  • if possible, drop the whole pygit2 dependency, if not used for anything left
• download MadGraph from its new source https://github.com/mg5amcnlo/mg5amcnlo (branch 3.4.1, see Download mg5amc using git pinecards#142)
• purge Breeze if not any longer used

[felixhekhorn]

latest release definetely

about which repos are we talking about? because all python stuff (eko, yadism) should come without repo (but via PyPI). If we're not using releases (everywhere) we could likewise give up on poetry ;-)

[alecandido]

PineAPPL and MadGraph. In particular, for PineAPPL we need to install the C API, and it's not a great idea to ship it as Python package (but maybe I'm just wrong...).

[scarlehoff]

It seems that to clone a repository from GitHub now you always need to set credentials, whatever URL you are using.

It should be possible to clone with no credentials. That said, agree with the following:

latest release definetely

[alecandido]

It should be possible to clone with no credentials.

I thought so as well (for public repositories of course), but I was not able to do it with pygit2 and GitHub...

Ok, let's go for latest then! (unless @cschwan is strongly against it...)

[felixhekhorn]

PineAPPL and MadGraph. In particular, for PineAPPL we need to install the C API, and it's not a great idea to ship it as Python package (but maybe I'm just wrong...).

I guess also vrap @scarlehoff ?

and to be more precise: let's not use latest, but a fixed version! to be specific for PineAPPL this would be import pineappl; pineappl.__version__ as defined by pyproject

[alecandido]

Ok, that might be fine as well

P.S.: for the non-python dependencies instead, I will hard-code versions in the package