Getting an optional string[] from the config seems more difficult than necessary - am I missing something?

let additionalZones: string[] = []
if (config.get('clusterAdditionalZones')) {
  additionalZones = config.get('clusterAdditionalZones')!.split(',')
}
export const clusterAdditionalZones = additionalZones

with config yml:

config:
  deployment:clusterAdditionalZones: us-central1-a,us-central1-b

I tried a string[] in the yaml and it rejected it with

line 7: cannot unmarshal !!seq into string

We don't yet support lists or maps in the Pulumi config yaml files, but it's on the roadmap. https://github.com/pulumi/pulumi/issues/2306