[FIX] mrp: date_planned_finished field correctly saved

When creating a MO _date_planned_finished_ is not added.
Consequently calculates wrongly the date planned to finish the MO.

X-original-commit: 2b2509e154af0e58a3f30f1d7fe40fb854b6b881
Part-of: odoo/odoo#84896

addons/mrp/models/stock_rule.py

@@ -104,6 +104,7 @@ class StockRule(models.Model):
             'bom_id': bom.id,
             'date_deadline': date_deadline,
             'date_planned_start': date_planned,
+            'date_planned_finished': fields.Datetime.from_string(values['date_planned']),
             'procurement_group_id': False,
             'propagate_cancel': self.propagate_cancel,
             'orderpoint_id': values.get('orderpoint_id', False) and values.get('orderpoint_id').id,