Do not rely on tar ball, allow user to specify command to generate src.rpm

You offer create_tarball_command and you hope that this tar ball will work with the upstream spec file. I experienced that sometimes the spec file is actually foo.spec.in and final spec files are generated by autotools. See https://github.com/abrt/abrt/blob/master/abrt.spec.in Or the generated tar ball does not work with the spec file as the spec file is altered during release process. E.g. https://github.com/rpm-software-management/mock/blob/devel/mock/mock.spec refers to Source: %{name}-%{version}.tar.gz but if you want to build from last commit, then you create tar ball using tito build --test --tgz which produces mock-git-55.17ed5ce.tar.gz. When I run tito build --srpm then tito automagically modify the spec file.

If you would offer something like create_srpm_command it would easy a lot of these things.

[xsuchy]

/me doing activity to please stale bot

[TomasTomecek]

I feel like we have reached a consensus within the team that we don’t want to support a custom srpm command. Is that true?

Therefore we should document for tito users how then can use packit in their projects.