ironic 15.0.0 release

meta:version: 15.0.0
meta:diff-start: -
meta:series: ussuri
meta:release-type: release
meta:pypi: no
meta:first: no
meta:release:Author: Sean McGinnis <sean.mcginnis@gmail.com>
meta:release:Commit: Julia Kreger <juliaashleykreger@gmail.com>
meta:release:Change-Id: I0b11aec1c4945b83b8883ec12659784420f4a201
meta:release:Code-Review+2: Thierry Carrez <thierry@openstack.org>
meta:release:Code-Review+1: Mark Goddard <mark@stackhpc.com>
meta:release:Workflow+1: Thierry Carrez <thierry@openstack.org>
meta:release:-  - Support for a hardware `retirement workflow <https://docs.openstack.org/ironic/latest/admin/retirement.html>`_ to enable automation of hardware decommission in managed clouds.
meta:release:+  - Support for a hardware `retirement workflow <https://docs.openstack.org/ironic/latest/admin/retirement.html>`_