Remove tests superseded by #504 and orphan 2021 expected-revenue files (part of #430 / #501 cleanup)

[donboyd5]

Summary

Deletes four categories of now-unused test artifacts from the skipped-tests cleanup that umbrella #501 described. This is the subset of that cleanup that can be done right now — items that depend on the still-to-be-written SOI sanity-check test are intentionally left in place for a follow-up pass.

What's removed

1. tests/test_tmd_stats.py + tests/tmd.stats-expect

Superseded by tests/test_tmd_file_fingerprint.py, which landed in #504. The new fingerprint test covers the same reproducibility-check role with a relative-tolerance comparison (rtol=1e-3) that absorbs cross-machine floating-point noise, instead of the exact-text diff of df.describe() output that caused test_tmd_stats.py to be skipped in the first place.

2. tests/tmd.stats-expect-github + tests/tmd.stats-expect-mrh

Alternate reference files that had been sitting alongside tmd.stats-expect. No live references anywhere in the repo — these were the artifacts of past debugging.

3. tests/expected_itax_rev_2021_data.yaml + tests/expected_ptax_rev_2021_data.yaml

Unreferenced orphan files. The live lookup in test_tax_revenue.py uses the 2022 YAMLs unconditionally (TAXYEAR=2022 is the only live key). Zero references in the repo confirmed by grep -r.

4. Docstring update in tests/test_tmd_file_fingerprint.py

Replaced the path-specific reference to tests/test_tmd_stats.py (now-deleted) with a past-tense description of the pattern it replaces, so the docstring stays accurate.

What's NOT in this PR

Intentionally left for the next round, which will be tracked in a separate focused issue (to be filed):

• tests/test_variable_totals.py + tests/taxdata_variable_totals.yaml — deletion depends on a new SOI sanity-check test replacing its external-benchmark role.
• test_misc.py::test_income_tax and its expected values — same; that SOI sanity-check subsumes the functionality.
• test_imputed_variables.py::test_imputed_variable_distribution — staying in place on assumption that @martinholmer prefers to keep it in place.

Test plan

• make format — clean (64 files unchanged).
• make lint — exit 0.
• make test — 59 passed, 4 skipped. Skip count is unchanged from before this PR, and includes the pre-existing skip markers on test_variable_totals, test_imputed_variable_distribution, test_tax_revenue. This change does not affect any currently-running test.
• Reference check: grep -r across the repo confirms none of the deleted files are referenced by anything still in the tree.

Related

• Handle the six skipped tests #430 — original triage of six skipped tests
• Plan for handling the remaining five skipped tests (follow-on to #430) #501 — umbrella plan for addressing them
• Add unweighted national-file fingerprint test (closes #503) #504 — the PR that landed the replacement fingerprint test (merged)
• Design discussion: future-year revenue sanity check — how to align tax-calculator iitax / payrolltax with a CBO or Treasury comparator #502 — sister design-discussion issue on future-year revenue comparator (open, independent)

After this PR merges, a short follow-up issue will be filed to track the remaining SOI-sanity-check work and its associated deletions, at which point #430 and #501 can both be closed.