This time, we cannot just delete the cluster. Such an action would leave the EBS volumes running. So, we need to remove them first.
We could remove EBS volumes through AWS CLI. However, there is an easier way. If we delete all the claims to EBS volumes, they will be deleted as well since our PersistentVolumes are created with the reclaim policy set to Delete. EBS volumes are created when needed and destroyed when not.
Since all our claims are in the jenkins Namespace, removing it is the easiest way to delete them all.