Remove legacy queries from get-flattened-publication script

[JimLarson]

What is the Problem Being Solved?

See #9096 for code at agoric-sdk/scripts/get-flattened-publication.sh, plus nearby tests.

Description of the Design

See parent issue.

Security Considerations

N/A

Scaling Considerations

N/A

Test Plan

Adjust unit tests for new interaction, manual testing against a test or local-net.

Upgrade Considerations

See parent issue

[JimLarson]

Note that the script needs to be updated to support smallcaps, so it doesn't work against live data. Issue #6311, draft PR #8028.

However, we can still fix the legacy query part of the script and test data.