ID income tax difference with TAXSIM35

[martinholmer]

The following integration test fails. It is not yet known whether the
tax logic problem is in TAXSIM35 or in the current PEUS code, or
whether there are problems in both models. This topic is meant to
facilitate discussion of why this test fails, primarily by reporting
the results of hand calculations required to fill out the relevant tax
form.

- name: Tax unit with taxsimid 58820 in k21.its.csv and k21.ots.csv
  absolute_error_margin: 0.01
  period: 2021
  input:
    people:
      person1:
        age: 56
        employment_income: 110010
        qualified_dividend_income: 1005.0
        taxable_interest_income: 5505.0
        short_term_capital_gains: 3505.0
        long_term_capital_gains: 1505.0
        rental_income: 1005.0
        taxable_private_pension_income: 2500.0
        real_estate_taxes: 4000
        mortgage_interest: 36000
        self_employment_income: 127010
        business_is_qualified: true
        business_is_sstb: false
        w2_wages_from_qualified_business: 100e6
        ssi: 0  # not in TAXSIM35
        state_supplement: 0  # not in TAXSIM35
        wic: 0  # not in TAXSIM35
        ma_covid_19_essential_employee_premium_pay_program: 0  # not in TAXSIM35
      person2:
        age: 56
        employment_income: 141010
        qualified_dividend_income: 1005.0
        taxable_interest_income: 5505.0
        short_term_capital_gains: 3505.0
        long_term_capital_gains: 1505.0
        rental_income: 1005.0
        taxable_private_pension_income: 2500.0
        ssi: 0  # not in TAXSIM35
        state_supplement: 0  # not in TAXSIM35
        wic: 0  # not in TAXSIM35
        ma_covid_19_essential_employee_premium_pay_program: 0  # not in TAXSIM35
    tax_units:
      tax_unit:
        members: [person1, person2]
        premium_tax_credit: 0  # not in TAXSIM35
        local_income_tax: 0  # not in TAXSIM35
        state_sales_tax: 0  # not in TAXSIM35
        ca_use_tax: 0  # not in TAXSIM35
        il_use_tax: 0  # not in TAXSIM35
        nm_2021_income_rebate: 0  # not in TAXSIM35
        nm_additional_2021_income_rebate: 0  # not in TAXSIM35
        nm_supplemental_2021_income_rebate: 0  # not in TAXSIM35
        ny_supplemental_eitc: 0  # not in TAXSIM35
        ok_use_tax: 0  # not in TAXSIM35
        pa_use_tax: 0  # not in TAXSIM35
        vt_renter_credit: 0  # not in TAXSIM35
        tax_unit_itemizes: True
        state_income_tax: 21664.05
    spm_units:
      spm_unit:
        members: [person1, person2]
        snap: 0  # not in TAXSIM35
        tanf: 0  # not in TAXSIM35
    households:
      household:
        members: [person1, person2]
        state_fips: 16  # ID
  output:  # expected results from patched TAXSIM35 2024-03-17 version
    id_income_tax: 21404.06

[PavelMakarchuk]

This is due to PE not applying the salt deduction reduction to the itemized deductions, will be fixed by #4239