feat: Update makefile to support building with podman

[anishasthana]

This PR will update the makefile and build scripts to allow developers to use podman as the build engine.
The default behaviour for the makefile will remain the same.

I ran the following to build images:

make build.develop ENGINE=podman
make build ENGINE=podman

I don't have a working docker env to test in.
cc @njhill

[njhill]

Thanks @anishasthana, this looks good to me. I thought docker aliased to podman anyhow though?

Should we also add --format=docker to the build command in the podman case?

[anishasthana]

It only happens if you've actually set up the alias ahead of time. I hadn't :-)

Should we also add --format=docker to the build command in the podman case?

I actually haven't used the --format=docker flag before -- never found the need to. There doesn't seem to be a major difference in the image specs.

[anishasthana]

I spoke to one of the podman maintainers. She said that the --format=docker is unnecessary unless there's something very specific to the docker format that our image requires. The OCI format is standard now and should be the default -- any runtimes that are OCI-compliant will work with OCI images.

[njhill]

It only happens if you've actually set up the alias ahead of time.

Ah interesting, the RHEL install I use had it already so I assumed it was configured by default.

I spoke to one of the podman maintainers. She said that the --format=docker is unnecessary unless there's something very specific to the docker format that our image requires. The OCI format is standard now and should be the default -- any runtimes that are OCI-compliant will work with OCI images.

OK sure, I just recall that I'd had to add it at some point in the past, maybe was for something obscure.

[kserve-oss-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: anishasthana, njhill

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [njhill]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[njhill]

/lgtm