Add architecture filtering support when mirroring content with oc-mirror

Story: As a user of disconnected OpenShift clusters I want to mirror content for a specific platform when multiple platforms are available.

Background: Allowing specific platforms/architectures to be mirrored would save disk space when mirroring content. There are some limitations currently when it comes to operators bundles: These limitations could be mitigated by:

1. Sparse manifest lists are allowed by registries
2. Multi-arch management moves into images that can be rewritten on mirror (i.e. the bundle images themselves, not the images referenced inside of the bundle images).
3. Allow ICSPs to mirror by tag

Acceptance criteria:

• oc mirror can mirror operator content for a specific architecture
• oc mirror can mirror custom images for a specific architecture