Label support for user namespaces (Owner, Division)

[vexingly]

Namespaces created by individual users need aggregation labels for kubecost, ideally these could be identified on creation (extracted from active directory?).

Support in kubecost for these labels already exists: https://gitlab.k8s.cloud.statcan.ca/cloudnative/terraform/modules/terraform-statcan-kubernetes-core-platform/-/blob/main/kubecost.tf

    owner_label: "project.statcan.gc.ca/lead"
    department_label: "project.statcan.gc.ca/division"