Description:
Upload-volume command fails when the volume was created from an image that was previously copied to other store.

A new cinder-tempest-plugin test case fails following these steps:
1. Deploy env with multistore enabled
2. Create an image on one of the available stores
3. Copy the image to the second store
4. Create a volume from that image
5. Upload the volume back to Glance

The volume was created (step 4) with these properties:
os_glance_failed_import
os_glance_importing_to_stores

The tempest log shows this error:

tempest.lib.exceptions.BadRequest: Bad request
Details: {'code': 400, 'message': "Unable to set 'properties' to {}. Reason: {} is not of type 'string'\n\nFailed validating 'type' in schema['additionalProperties']:\n {'type': 'string'}\n\nOn instance['properties']:\n {}"}

The properties were filtered out as indicated in cinder-api log:
2026-01-06 19:52:24.357 18 DEBUG cinder.image.image_utils [req-b11ba6bf-c78e-4d24-be10-a1fc468fccd7 02e23254ad614f1f8a8a1f0e36c971ae b637773ab7394b3db925f85ff2991b6d - default default] The metadata set [\{'container_format': 'bare', 'disk_format': 'raw', 'name': 'test-image-from-vol', 'properties': {'owner_specified.openstack.sha256': '', 'os_glance_importing_to_stores': '', 'os_glance_failed_import': '', 'owner_specified.openstack.object': 'images/cirros-test-img', 'signature_verified': 'False', 'owner_specified.openstack.md5': ''}}] was filtered using the reserved name spaces [['os_glance', 'img_signature']], and the result is [\{'container_format': 'bare', 'disk_format': 'raw', 'name': 'test-image-from-vol', 'properties': {'owner_specified.openstack.sha256': '', 'owner_specified.openstack.object': 'images/cirros-test-img', 'signature_verified': 'False', 'owner_specified.openstack.md5': ''}}]. filter_out_reserved_namespaces_metadata /usr/lib/python3.9/site-packages/cinder/image/image_utils.py:1334

Additional info:
Red Hat OpenStack Platform release 17.1.12 (Wallaby)
openstack-cinder-18.2.2-17.1.20250929130805.f6b44fc.el9ost.noarch