Adds Deployment Data Source

[itmecho]

I had a need to load a deployment from kubernetes to use the currently running container image in my terraform resource. This PR adds the kubernetes_deployment data source.

I ran the acceptance test against minikube and have used the data source with my current kubernetes setup (running on AWS) and it seems to be working as intended.

This is my first time working in this repo so any tips/errors I made would be great to know!

[sl1pm4t]

Hi @itmecho - thanks for the PR and sorry for the delay getting to it.

This looks good, but I have one suggetion that will make the datasource more easily maintainable going forward. We can leverage some code I added to the Google provider a while back, that can generate datasource schema definition from a resource:
See
https://github.com/terraform-providers/terraform-provider-google/blob/2.0.0/google/datasource_helpers.go

and this is an example datasource that uses the above:

https://github.com/terraform-providers/terraform-provider-google/blob/2.0.0/google/data_source_google_container_cluster.go

Are you OK to implement this?
Thanks

[sl1pm4t]

Thanks!

[itmecho]

Awesome, Thanks!