publish: Use podman push instead of skopeo copy to push images

[brianmcarey]

What this PR does / why we need it:

The publish postsubmit is no longer using docker to build and publish the kubevirtci images[1] so therefore the skopeo workaround is no longer required.

podman push is the simpler option to go for.

[1] https://github.com/kubevirt/project-infra/commit/1229020479c3317f8c8e68aa92fde2cb5cc0aec9

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged): Fixes #

Special notes for your reviewer: /cc @dhiller

Checklist

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• [ ] Design: A design document was considered and is present (link) or not required
• [ ] PR: The PR description is expressive enough and will help future contributors
• [ ] Code: Write code that humans can understand and Keep it simple
• [ ] Refactor: You have left the code cleaner than you found it (Boy Scout Rule)
• [ ] Upgrade: Impact of this change on upgrade flows was considered and addressed if required
• [ ] Testing: New code requires new unit tests. New features and bug fixes require at least on e2e test
• [ ] Documentation: A user-guide update was considered and is present (link) or not required. You want a user-guide update if it's a user facing feature / API change.
• [ ] Community: Announcement to kubevirt-dev was considered

Release note:

[kubevirt-bot]

Skipping CI for Draft Pull Request. If you want CI signal for your change, please convert it to an actual PR. You can still manually trigger a test run with /test all

[kubevirt-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: dhiller

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[kubevirt-bot]

@brianmcarey: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
check-up-kind-1.27-vgpu	10972bdd89db035874b32c29752aaf96e931cd12	link	false	/test check-up-kind-1.27-vgpu

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[brianmcarey]

/hold cancel

nit addressed