Add explicit pull and tag and push to the minikube image command

[afbjorklund]

These come in handy sometimes, for instance when testing. Currently included as part of other commands:

minikube image load --pull docker.io/my/image:v1.2.3

minikube image build --tag docker.io/my/image:latest --push

These are added to the cruntime API, and then exposed in the minikube image CLI for use in the tests.

[afbjorklund]

Note that we still want "build" to handle it internally, to be able to support future features like multi-arch.

The original specification only allows for one architecture, so one can't use tags to handle manifests...

But BuildKit can handle multiple arch.

Might be a feature in Podman 4.0, too.