fix(sp41): drop unused Decimal import from pipeline_b

backend/src/cyclone/rebill/pipeline_b.py

@@ -11,7 +11,6 @@ override flag is the same for the whole batch (a per-batch override).
 from collections import defaultdict
 from dataclasses import dataclass
 from datetime import date
-from decimal import Decimal
 from pathlib import Path
 
 from cyclone.rebill.reconcile import VisitRow