Fix for incorrect "previous_month" logic in [last_month] field

Released: May 28, 2025

The last_month field in the drp.calendar table is currently returning values from the same month of the previous year instead of the previous month of the current year for the previous_month category.

Update the logic for the previous_month category to correctly reference the previous calendar month within the current year in the drp.calendar table. This will ensure accurate time-based categorizations for reporting and analysis.