[fix] add missing import

report/product_pricelist_report.py

 # Copyright 2021 Le Filament (<http://www.le-filament.com>)
 # License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html).
 
+from odoo import models
+
 
 class report_product_pricelist(models.AbstractModel):
     _inherit = 'report.product.report_pricelist'