[FIX] hr_expense: fix 'hr.expense' has no attribute 'attach_document'​

In case hr_expense_extract is not installed and we click
'Attach Receipt' on hr_expense form view, we get a traceback.

task - 2870500

closes odoo/odoo#92761

X-original-commit: 8593decb2fe6820cfc6f043cb3458f43dd635c87
Signed-off-by: Kevin Baptiste <kba@odoo.com>

addons/hr_expense/models/hr_expense.py

@@ -121,6 +121,9 @@ class HrExpense(models.Model):
     sample = fields.Boolean()
     label_convert_rate = fields.Char(compute='_compute_label_convert_rate')
 
+    def attach_document(self, **kwargs):
+        pass
+
     @api.depends('product_has_cost')
     def _compute_currency_id(self):
         for expense in self.filtered("product_has_cost"):