fix: include current month full tax in total income tax and current m…

[Sudharsanan11]

Issue:
the current month's full tax is not included in the total income tax and the current month's tax amount

Current Calculation:

      Tax Regime - New Tax Regime
      additional salary(full tax) - 1,00,000
      monthly salary - 1,00,000
      annual salary - 12,00,000

      total earnings - 13,00,000
      total taxable  - 12,25,000
      tax without full tax - 71,500
      tax with full tax - 88,400
      full tax: 88,400 - 71,500 = 16,900
       
      monthly structured tax - 71,500/12 - 5,958.33
      currency month tax: 16900 + 5958.33 = 22,858.33

      future tax deductions: 71,500 - 22,858.33 = 48,641.67
      total income tax: 48,641.67(future tax) + 22,858.33(tax deducted till date) = 71,500

Updated Calculation:

      Tax Regime - New Tax Regime
      additional salary(full tax) - 1,00,000
      monthly salary - 1,00,000
      annual salary - 12,00,000

      total earnings - 13,00,000
      total taxable  - 12,25,000
      tax without full tax - 71,500
      tax with full tax - 88,400
      full tax: 88,400 - 71,500 = 16,900
       
      monthly structured tax - 71,500/12 - 5,958.33
      currency month tax: 16900 + 5958.33 = 22,858.33

      future tax deductions: 71,500 - 22,858.33 = 48,641.67
      total income tax: 48,641.67(future tax) + 22,858.33(tax deducted till date) + 16,900(full tax) = 88,400

Additional Salary:

Earnings and Deductions:

Before:

After:

Backport needed for v14 & v15