Allow changing the image format of the uploaded image

[Gabriel Samfira]

After the image is retrofited, we need to be able to set the image format to be uploaded back to Glance. On systems that leverage Ceph or any other storage appliance that uses raw as its native storage format, this allows fast CoW VM disk creation. It also means that if force-raw-images is set to true, nova will no longer download the image, convert it to raw and copy it to the storage backend before creating the
VM. This saves a lot of bandwidth and time.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/openstack/charm-octavia-diskimage-retrofit/+/896680

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/openstack/charm-octavia-diskimage-retrofit/+/896680
Committed: https://opendev.org/openstack/charm-octavia-diskimage-retrofit/commit/1f44f44d0ed708e2f58e34fc3beb48bd3c01a2e1
Submitter: "Zuul (22348)"
Branch: master

commit 1f44f44d0ed708e2f58e34fc3beb48bd3c01a2e1
Author: Gabriel Adrian Samfira <email address hidden>
Date: Wed Sep 27 17:50:10 2023 +0300

    Allow setting the image format of the image

    After the image is retrofited, we need to be able to set the image
    format to be uploaded back to Glance. On systems that leverage Ceph or
    any other storage appliance that uses raw as its native storage format,
    this allows fast CoW VM disk creation. It also means that if
    force-raw-images is set to true, nova will no longer download the image,
    convert it to raw and copy it to the storage backend before creating the
    VM. This saves a lot of bandwidth and time.

    Closes-Bug: #2037557

    Change-Id: I4eb62e330584635ccecd06c9ccac691723ea20b7
    Signed-off-by: Gabriel Adrian Samfira <email address hidden>