Documentation Link: https://docs.openshift.com/container-platform/4.16/installing/installing_with_agent_based_installer/understanding-disconnected-installation-mirroring.html#configuring-the-agent-based-installer-to-use-mirrored-images

The link above refers to the use of imageContentSources to configure the repository mirror.Since the oc-mirror plugin now works with Image digest sources should it refer users to configure ImageDigestSources in the install config.yaml instead of imagecontentsources

i.e Like this
ImageDigestSources:
  - mirrors:
    - rhel-idm.tide.lan:8443/ocp4/ubi8
    source: registry.redhat.io/ubi8

Instead of
ImageContentSources:
  - mirrors:
    - rhel-idm.tide.lan:8443/ocp4/ubi8
    source: registry.redhat.io/ubi8

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