node metadata check failing

[wyardley]

% inspec exec inspec-gke-cis-gcp --controls cis-gke-5.4.2-node-metadata -t gcp:// --input-file inputs.yml --reporter cli
[...]
  ×  cis-gke-5.4.2-node-metadata: [NODE-METADATA] Ensure the GKE Metadata Server is Enabled
     ×  [twicapp-production] Cluster us-west2/prod-cluster-01, Node Pool: default-node-pool config.workload_meta_config.mode is expected to be in "GCE_METADATA" and "GKE_METADATA"
     expected `` to be in the list: `["GCE_METADATA", "GKE_METADATA"]`

dumping out the config object, it's got:

     +     "workloadMetadataConfig"=>{"mode"=>"GKE_METADATA"},

the GCP CLI also shows

config:
  workloadMetadataConfig:
    mode: GKE_METADATA

I'm guessing this is either an upstream issue with https://github.com/inspec/inspec-gcp, or with the old version of it vendored in at https://github.com/GoogleCloudPlatform/inspec-gcp-helpers/, but this is all nested enough that it's hard to know exactly where to file a report, or what's to blame.

I verified that the workload_meta_config.mode (vs metadata) is supposed to be the right attribute name.