Description of problem:

A procedure for scanning for deprecated internal images should be added to section 'Updating deprecated internal images' of Troubleshooting.
https://docs.openshift.com/container-platform/4.9/migrating_from_ocp_3_to_4/troubleshooting-3-4.html#migration-updating-deprecated-internal-images_troubleshooting-3-4
Additional info:
Here is a command that can be run to output potentially problematic builds:

oc get bc --all-namespaces --template='range .items
"BuildConfig:" .metadata.namespace/.metadata.name =>
"\t""ImageStream(FROM):" .spec.strategy.sourceStrategy.from.namespace/.spec.strategy.sourceStrategy.from.name
"\t""ImageStream(TO):" .spec.output.to.namespace/.spec.output.to.name
end'