Use az acr import for Azure Container Registries promotions

[lenardchristopher]

For all registries, we currently using a generic OCI image promotion -- pull, tag, push. With Azure Container Registries, memory and performance can be improved using az acr import. https://docs.microsoft.com/en-us/cli/azure/acr?view=azure-cli-latest#az_acr_import

Implementing this will require a provider abstraction in the image processor that will swap in the azure logic when working with an ACR.