To Reproduce Steps to reproduce the behavior:

1. Install RHOSP 17.1 with Octavia [1].
2. Enable Image verification of signature [2].
3. Create a new load balancer.
4. See error: 
    File "/usr/lib/python3.9/site-packages/nova/compute/manager.py", line 2330, in _do_build_and_run_instance\n self._build_and_run_instance(context, instance, image,\n File "/usr/lib/python3.9/site-packages/nova/compute/manager.py", line 2598, in _build_and_run_instance\n raise exception.BuildAbortException(instance_uuid=instance.uuid,\nnova.exception.BuildAbortException: Build of instance 058c9f29-8c1f-4628-9e31-92b88037b487 aborted: Signature verification for the image failed: Required image properties for signature verification do not exist. Cannot verify signature. Missing property: img_signature_hash_method.\n
    

Expected behavior

• Be able to create load balancers after enabling Image verification of signature.

Device Info (please complete the following information):

• RHOSP 17.1.8
• OS Version: 9.2

Bug impact

• Customer is unable to create or manage running loadbalancer because of not signed image.

Known workaround

• Disable image verification.

Additional context

• [1] https://docs.redhat.com/en/documentation/red_hat_openstack_platform/17.1/html/configuring_load_balancing_as_a_service
• [2]https://docs.redhat.com/en/documentation/red_hat_openstack_platform/17.1/html-single/managing_secrets_with_the_key_manager_service/index#proc-validating-image-service-images_key-manager-services
• Looks like all images are verified and customized Amphora images are not supported because this image is update by deployment.