Merge tag '2.8.0' into debian/yoga

oslo.service 2.8.0 release

meta:version: 2.8.0
meta:diff-start: -
meta:series: yoga
meta:release-type: release
meta:pypi: yes
meta:first: no
meta:release:Author: Hervé Beraud <hberaud@redhat.com>
meta:release:Commit: Hervé Beraud <hberaud@redhat.com>
meta:release:Change-Id: I0d1110ef372d24155977a2a3262ec3ea8098dccd
meta:release:Code-Review+1: Lajos Katona <katonalala@gmail.com>
meta:release:Code-Review+1: Rodolfo Alonso <ralonsoh@redhat.com>
meta:release:Code-Review+2: Elod Illes <elod.illes@est.tech>
meta:release:Code-Review+2: Thierry Carrez <thierry@openstack.org>
meta:release:Workflow+1: Thierry Carrez <thierry@openstack.org>