Previously we would rely on auto-compilation of all the Guix modules.
The complete evaluation would take ~15mn on berlin.guixsd.org and
require lots of RAM. This approach should be faster since potentially
only part of the modules are rebuilt. Furthermore, as a side-effect, it
builds the derivations that 'guix pull' uses.
* build-aux/hydra/gnu-system.scm: Remove 'eval-when' form.
(hydra-jobs): New procedure.
* gnu/ci.scm (package->alist, qemu-jobs, system-test-jobs)
(tarball-jobs): Return strings for the 'license' field.
* guix/self.scm (compiled-guix)[*cli-modules*]: Add (gnu ci).