make obs-publish: Don't publish Debian packages

This requires actually building the "debian-src-pkg" folder, which
requires a Debian machine. The Debian packages don't actually build
anyway, because the dependencies aren't met on current Debian
stable (and OBS doesn't build packages for Debian testing).
make obs-publish: Don't fail if OBS package doesn't exist yet

(For example if you run `make obs-publish OBS_PROJECT=my-new-project`.)
rpm spec file: Add missing dependency "moreutils"

For the "ts" command, used by "stbt batch run".

Note that on some OSs the moreutils package is a pain because it
contains a utility called "parallel" which conflicts with GNU parallel
from the "parallel" package. However on Fedora the moreutils version
is shipped separately in the "moreutils-parallel" package.