build_table returns (table, reverts_column, wikitext_parser) but the
jsonl test helper still unpacked two values, so test_jsonl_noargs and
test_jsonl_tsv_equivalence failed with a ValueError before reading any
output. Also update the docstring, which still described the two-value
return.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
(cherry picked from commit 7c27942cb0)