refactor(scanner): separate GetImage from ToDirectory

[akijakya]

So if the image metadata is also needed, we don't get the image twice.

Description

Put getting the image in a separate function so that if the image metadata is also needed outside of extracting it to a directory, we don't need to get the image twice.

Type of Change

• [ ] Bug Fix
• [ ] New Feature
• [ ] Breaking Change
• [X] Refactor
• [ ] Documentation
• [ ] Other (please describe)

Checklist

• [X] I have read the contributing guidelines
• [ ] Existing issues have been referenced (where applicable)
• [X] I have verified this change is not present in other open pull requests
• [ ] Functionality is documented
• [ ] All code style checks pass
• [ ] New code contribution is covered by automated tests
• [ ] All new and existing tests pass

[github-actions[bot]]

Hey!

Your images are ready:

• ghcr.io/openclarity/vmclarity-apiserver-dev:pr1823-8a21d7a18d3b8bd5e4c52c09dc7763e46765e1c3
• ghcr.io/openclarity/vmclarity-cli-dev:pr1823-8a21d7a18d3b8bd5e4c52c09dc7763e46765e1c3
• ghcr.io/openclarity/vmclarity-cr-discovery-server-dev:pr1823-8a21d7a18d3b8bd5e4c52c09dc7763e46765e1c3
• ghcr.io/openclarity/vmclarity-orchestrator-dev:pr1823-8a21d7a18d3b8bd5e4c52c09dc7763e46765e1c3
• ghcr.io/openclarity/vmclarity-plugin-kics-dev:pr1823-8a21d7a18d3b8bd5e4c52c09dc7763e46765e1c3
• ghcr.io/openclarity/vmclarity-ui-dev:pr1823-8a21d7a18d3b8bd5e4c52c09dc7763e46765e1c3
• ghcr.io/openclarity/vmclarity-ui-backend-dev:pr1823-8a21d7a18d3b8bd5e4c52c09dc7763e46765e1c3