Support regional clusters

[matt-simons]

Presently google_container_cluster only supports zonal clusters as it uses the get_zone_cluster function in https://github.com/googleapis/google-api-ruby-client/blob/master/generated/google/apis/container_v1beta1/service.rb

If instead it used get_project_location_cluster it would support both zonal and regional clusters.

Similarly google_container_clusters could support both zonal and regional clusters if it used list_project_location_clusters function.

Happy to create a pull request to resolve this.

[skpaterson]

Thanks @matt-simons that makes good sense. PR's are always welcome! Otherwise will happily pick this up at the next opportunity.

[pinterb]

I've got something coded to support regional clusters. I'm new to both Inspec and Ruby, so I'd like to dogfood it a bit first.

[slevenick]

Now available here: https://github.com/inspec/inspec-gcp/blob/master/libraries/google_container_regional_cluster.rb

And https://github.com/inspec/inspec-gcp/blob/master/libraries/google_container_regional_clusters.rb

[skpaterson]

Thanks @slevenick ! @pinterb I'll close this out but feel free to reopen if you encounter any issues.