[CCLM] Got mac address conflicts when stop the source VM during the migration

CNV 4.20.0-135

Always

1. Create a source VM in cluster1
2. Migrate the VM to cluster2
3. Stop the VM during the migration

a. If we stop the source vm when the target VM is just prepared and the migration progress is not started yet. 

source vmim is not existing and target vmim is in WaitingForSync phase.
$ oc get vmim
NAME             PHASE            VMI
forklift-kwrg2   WaitingForSync   centos


b. If we stop the source vm when the target VM is migrating, both VMIM is just running:
source vmim
$ oc get vmim
NAME             PHASE     VMI
forklift-jw7fm   Running   centos

target vmim
$ oc get vmim 
NAME             PHASE         VMI
forklift-nzqnt   TargetReady   centos

source vm 
$ oc get vm
NAME      AGE     STATUS    READY
centos    11h     Stopped   False

target vm
$ oc get vm
NAME      AGE    STATUS     READY
centos    26m    Starting   False

c. If we stop the source vm when the target VM has been migrated for a few seconds, maybe closed to finish the migration
source vmim
$ oc get vmim is running and then gone after the migration finished
NAME             PHASE     VMI
forklift-rmj9f   Running   centos2

target vmim
$ oc get vmim
NAME             PHASE         VMI
forklift-d9r2c   Succeeded     centos2

Have a better way to handle the situation that the source vm becomes stopped during the migration