The image cannot be deleted because it is in use through the backend store outside of Glance in Red Hat OpenStack Platform 13 with Red Hat Ceph Storage 3

Issue

And image stored in Ceph cannot be deleted. The Error message in the glance logs is:

[root@overcloud-controller-0 glance]# grep -Ri req-9c632cce-5435-4d5e-8fb9-560a52a11326 .
./api.log:2019-08-19 20:51:18.532 32 ERROR glance_store._drivers.rbd [req-9c632cce-5435-4d5e-8fb9-560a52a11326 06c8ffa75e2d4b758b99b9a89271a3a6 f525a9ac18d44aed9318155500d3c0c6 - default default] Snap Operating Exception [errno 16] error unprotecting snapshot da32d552-7c9f-4a10-b581-cc82b870ad96@snap Snapshot is in use.: ImageBusy: [errno 16] error unprotecting snapshot da32d552-7c9f-4a10-b581-cc82b870ad96@snap
./api.log:2019-08-19 20:51:18.536 32 WARNING glance.api.v2.images [req-9c632cce-5435-4d5e-8fb9-560a52a11326 06c8ffa75e2d4b758b99b9a89271a3a6 f525a9ac18d44aed9318155500d3c0c6 - default default] Image da32d552-7c9f-4a10-b581-cc82b870ad96 could not be deleted because it is in use: The image cannot be deleted because it is in use through the backend store outside of Glance.: InUseByStore: The image cannot be deleted because it is in use through the backend store outside of Glance.
./api.log:2019-08-19 20:51:18.537 32 INFO eventlet.wsgi.server [req-9c632cce-5435-4d5e-8fb9-560a52a11326 06c8ffa75e2d4b758b99b9a89271a3a6 f525a9ac18d44aed9318155500d3c0c6 - default default] 10.199.92.20 - - [19/Aug/2019 20:51:18] "DELETE /v2/images/da32d552-7c9f-4a10-b581-cc82b870ad96 HTTP/1.1" 409 488 0.240100