fix path to experimental pack binaries

[sophiewigmore]

Summary

The latest version of skopeo on Ubuntu 22.04 isn't up-to-date enough to have multi-arch push support, so use crane instead

Use Cases

Checklist

• [ ] I have viewed, signed, and submitted the Contributor License Agreement.
• [ ] I have linked issue(s) that this PR should close using keywords or the Github UI (See docs)
• [ ] I have added an integration test, if necessary.
• [ ] I have reviewed the styleguide for guidance on my code quality.
• [ ] I'm happy with the commit history on this PR (I have rebased/squashed as needed).