Bridge to convert from compose.yaml to HELM values

[jjallaire]

We want evals written with compose.yaml to be runnable directly on the k8s sandbox. This is that the community built evals which use Docker compose don't require adaptation and updating for running on k8s (as this is both time consuming and possibly error prone).

[craigwalton-dsit]

Linking this up with the issue on the k8s_sandbox repo which has some more context UKGovernmentBEIS/inspect_k8s_sandbox#10