Changes

upstream-ci: test upstream kdump builds against FCOS

In an effort to reduce kdump issues, let's run our tests against their
upstream repo, to catch problems earlier.

See https://github.com/rhkdump/kdump-utils/pull/62
Also: https://issues.redhat.com/browse/RHEL-70438

jenkins/config: allow rhkdump org members to cancel and retrigger runs

Ideally these ACLs would be finer-grained still so that each org members
can only affect jobs related to their orgs. But OTOH cancelling and
retriggering tests doesn't have to be a super privileged action anyway.