We have to save raw blocks to the snapshot, but we should not be scanning them
for additional links as if they were CBOR blocks.
This cleans the logic a bit (we were checking that the parent was a CBOR block
before queueing up the children, but then scanning the children... it was weird).
Additionally, more verbose logging is added for the next time ScanForLinks
fails (currently very little info was given).
Our ScanForLinks callback should only enqueue CBOR for further processing.
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