[testing] snapshot tests with container images

[prabhu]

We can use the bulk-generate script as a starting point to implement snapshot testing with container images. Such tests are more portable compared to our current cli snapshot tests which requires a specific internal runner (snapshot-test $$$).

https://github.com/CycloneDX/cdxgen/tree/master/contrib/bulk-generate

We can utilize the new ['macos-hosted', 'arm64'] self-hosted runner.