The enhancement that was tracked in this card: https://issues.redhat.com/browse/CNV-37843

Introduced a new flag for virtctl vmexport: "--delete-vme" 

From rh-ee-alromero's fix PR description: 

Before this PR:

The virtctl vmexport download command always deleted the vmexport resources after exiting. This behavior wasn't ideal since we could be potentially deleting resources created in advance. This behavior could be improved.

After this PR:

Now the command will delete vmexport resources by default when the download command creates them itself. However, the resources will be retained if they were created in advance.

A new, -delete-vme flag has been included to allow deleting the vmexport everytime the download exits. -keep-vme does the opposite, so we can retain the vmexport resource even when the command creates it.

Fixes # #11080