Add flag to target optional docker repo

Can we add a feature/flag to target another (on prem/ personal mirror) docker hub
My very basic test.yaml:

> `schemaVersion: 2.0.0
> commandTests:
> - name: "cacheTest"
> command: "ls"
> args: ["/home/developer/.cache"]
> expectedOutput: ["2.2.*.*.txt"]`

Command run :
'docker run gcr.io/gcp-runtimes/container-structure-test:latest test --driver tar --image localhost/test-local:test --config /test.yaml'

is giving me the following error
`Error: error creating driver: retrieving image: retrieving remote image: Get "https://index.docker.io/v2/": dial tcp: lookup index.docker.io on 10.0.2.3:53: no such host`