[IMP]sale_*: Improvement in model description

Purpose of this commit is to give description more "business oriented"
because those descriptions appears in Odoo Studio which is supposed to be used by end users, not only by developers.

Related Task ID : 37311

report/sale_coupon_report.py

@@ -6,6 +6,7 @@ from odoo import api, models
 
 class CouponReport(models.AbstractModel):
     _name = 'report.sale_coupon.report_coupon'
+    _description = 'Sales Coupon Report'
 
     @api.model
     def _get_report_values(self, docids, data=None):

wizard/sale_coupon_apply_code.py

@@ -7,6 +7,7 @@ from odoo.exceptions import UserError
 class SaleCouponApplyCode(models.TransientModel):
     _name = 'sale.coupon.apply.code'
     _rec_name = 'coupon_code'
+    _description = 'Sales Coupon Apply Code'
 
     coupon_code = fields.Char(string="Coupon", required=True)
 

wizard/sale_coupon_generate.py

@@ -6,6 +6,7 @@ from odoo.tools.safe_eval import safe_eval
 
 class SaleCouponGenerate(models.TransientModel):
     _name = 'sale.coupon.generate'
+    _description = 'Sales Coupon Generate'
 
     nbr_coupons = fields.Integer(string="Number of Coupons", help="Number of coupons", default=1)
     generation_type = fields.Selection([