ci: use `runAsUser: 0` instead of `privileged: true`
It's the same thing for now for backwards compatibility, but privileged
has a different connotation from "running as uid 0". See for details:
@Library('github.com/coreos/coreos-ci-lib@master') _
-coreos.pod([image: 'registry.fedoraproject.org/fedora:30', privileged: true, kvm: true]) {
+coreos.pod([image: 'registry.fedoraproject.org/fedora:30', runAsUser: 0, kvm: true]) {
checkout scm
stage("Build") {
