[FIX] hr_expense: error on duplication with uom

Step to reproduce:
- Duplicate expense with a uom != of Unit

Current behaviour :
- Error telling that the unit is not correctly chosen

Behaviour After PR:
- The uom is copied on duplication and no error

opw-2714136

closes odoo/odoo#81973

X-original-commit: bd4db173284aa45d141cc3736ecef511738dd8e3
Signed-off-by: Damhaut Florian (flda) <flda@odoo.com>

addons/hr_expense/models/hr_expense.py

@@ -64,7 +64,7 @@ class HrExpense(models.Model):
     # product_id not required to allow create an expense without product via mail alias, but should be required on the view.
     product_id = fields.Many2one('product.product', string='Category', readonly=True, tracking=True, states={'draft': [('readonly', False)], 'reported': [('readonly', False)], 'refused': [('readonly', False)]}, domain="[('can_be_expensed', '=', True), '|', ('company_id', '=', False), ('company_id', '=', company_id)]", ondelete='restrict')
     product_uom_id = fields.Many2one('uom.uom', string='Unit of Measure', compute='_compute_from_product_id_company_id',
-        store=True, states={'draft': [('readonly', False)], 'refused': [('readonly', False)]},
+        store=True, copy=True, states={'draft': [('readonly', False)], 'refused': [('readonly', False)]},
         default=_default_product_uom_id, domain="[('category_id', '=', product_uom_category_id)]")
     product_uom_category_id = fields.Many2one(related='product_id.uom_id.category_id', readonly=True, string="UoM Category")
     unit_amount = fields.Float("Unit Price", compute='_compute_from_product_id_company_id', store=True, required=True, copy=True,