rename StockPicking class to SMCStockPicking to avoid namespace clashes

models/dp_shipping_service.py

@@ -21,7 +21,7 @@ class SMCShippingDpService(models.Model):
     international = fields.Boolean("International", required=1)
 
 # extend stock.picking with fields for Shipment and Voucher ID
-class StockPicking(models.Model):
+class SMCStockPickingDp(models.Model):
     _inerit = "stock.picking"
     dp_shipping_number = fields.Char(string="DP Shipment ID")
     dp_voucher_number = fields.Char(string="DP Voucher ID")