Add selectableFields to NodeMaintenance

[adrianchiris]

What would you like to be added?

in k8s 1.31 selectableFields for CRD was promoted to stable[1]
once controller tools support selectable fields [2] we should use the defined markers to add the following selectable fields to NodeMaintenance CRD:

spec:
  selectableFields:
  - jsonPath: .spec.requestorID
  - jsonPath: .spec.nodeName

this will allow to list NodeMaintenance by requestorID and nodeName.

[1] https://kubernetes.io/docs/tasks/extend-kubernetes/custom-resources/custom-resource-definitions/#crd-selectable-fields
[2] kubernetes-sigs/controller-tools#1039