Should re-connect container images that are used again

[cben]

https://bugzilla.redhat.com/show_bug.cgi?id=1488072

(extracting from ManageIQ/manageiq#14808 which was an unacceptable solution, so we can track the bug)
If refresh archives a container image record and later refresh encounters same image again, we create a duplicate record. This can be confusing in reports.

We don't see this much when images come from openshift registry, as these stay around for a long time.
Scenarios where we may disconnect an image not currently used in any container:

• a Kubernetes provider
• Openshift provider that run images from external registries
• Openshift dropping the image from /oapi/v1/images e.g. by pruning
• Openshift configured get_container_images: false (Add config option to skip container_images manageiq#14606)
• Openshift configured store_unused_images: false (Option needed for new ems_refresh.openshift.store_unused_images setting #11 + Add ems_refresh.openshift.store_unused_images setting manageiq-providers-openshift#9)
• Openshift fetching used images one by one (if Container image post refresh from openshift manageiq#14628 gets revived)

[simon3z]

@cben we probably need better tracking of this RFE, if you file a BZ it wont go unnoticed (please do file a BZ 😄 )

[cben]

Should be fixed for graph refresh by #145.

Left unfixed in save_inventory refresh as we never found an acceptably efficient fix. (This is our first deliberate behavior divergence between old vs graph refresh.)