// The v1.22+ in-tree implementations of the well-known Kubernetes signers will
  // honor this field as long as the requested duration is not greater than the
  // maximum duration they will honor per the --cluster-signing-duration CLI
  // flag to the Kubernetes controller manager.
  //
  // Certificate signers may not honor this field for various reasons:
  //
  //   1. Old signer that is unaware of the field (such as the in-tree