packit: Use upstream tarball for release COPR build
packit: Use upstream tarball for release COPR build

Current packit defaults to runing the `create-archive:` action for
release copr_builds. It should rather behave like `propose_downstream:`
and download the official release tarball from the spec's `Source0:`, as
this is conceptually much closer to releasing to Fedora than building a
temporary COPR for a PR.

This is currently being discussed in
https://github.com/packit/packit-service/issues/1505 , and this is the
recommended workaround until this becomes the default.

t# interactive rebase in progress; onto 155f2799d

mvollmer/cockpit,mvollmer/cockpit,mvollmer/cockpit,cockpit-project/cockpit,martinpitt/cockpit,martinpitt/cockpit,martinpitt/cockpit,cockpit-project/cockpit,martinpitt/cockpit,martinpitt/cockpit,mvollmer/cockpit,cockpit-project/cockpit,mvollmer/cockpit,cockpit-project/cockpit,cockpit-project/cockpit