feat: Add optional `--update-apt-cache` and `--rootdir-architecture` arguments to force apt cache update

[philroche]

To ensure apt cache is present we can either run apt-get update in a mounted filesystem ourselves using chroot or cpc-sbom can now do so using --update-apt-cache. This will require cpc-sbom to be run as root.

--rootdir-architecture optional flag allows us to ensure that the apt cache uses the correct architecture when mounting a non amd64 filesystem.

[SamirPS]

LGTM