load: kind load docker-image .. is non-functional for provider podman

[flouthoc]

As of now kind hardcodes looking and loading images from docker
as a result kind load docker-image : does not works well when
Provider is configured as podman instead of docker.

Following PR makes sure that kind supports loading images irrespective of
the providers configured and works for both podman and docker

What happened:
kind load docker-image <image-name>:<image-tag> is not functional when provider is configured as podman.

What you expected to happen:
To get image uploaded into control-plane

How to reproduce it (as minimally and precisely as possible):

[root@fedora ~]# kind load docker-image localhost/test:latest
enabling experimental podman provider
ERROR: image: "localhost/test:latest" not present locally

Anything else we need to know?:
I think this can be fixed by: #2728

[BenTheElder]

it is expected that kind load docker-image only supports ... docker, docker is in the name

#2038 for the tracking issue re: we should have a multi-provider option.

in the meantime: podman save image | kind load image-archive -

[flouthoc]

@BenTheElder Thanks for promptly replying. Ah i see if there is already a plan for unification of image command then that would be better. Podman still supports docker-image format but command is a no-op when docker is not present on the host hence I thought it would be better to use whatever provider is present.

I can use my patch or a workaround till this is fixed upstream. This issue is not a blocker for my use-case so its perfectly fine to wait for unification of image command.

Please feel free to close this issue if this is already being tracked somewhere to avoid redundancy.

Cheers 😄