tests(moarstats): Update expected output as we now use more accurate FMA

Refresh expected CSV strings in tests/test_moarstats.rs to match updated statistical results. Updated expectations in multiple test functions (moarstats_basic_with_existing_stats, moarstats_advanced, moarstats_advanced_atkinson_epsilon) — e.g. adjusted values for case_enquiry_id, open_dt and related computed metrics — so the tests align with recent changes to the stats calculations.

Author: jqnatividad