Remove old code from 'discontinued' product attribute
CHANGELOG:
### Fixed
- [#776](https://gitlab.com/coopdevs/odoo-somconnexio/-/merge_requests/776) Remove old code from 'discontinued' product attribute
Related card: -
Related error:
ValueError: Invalid field 'discontinued' in leaf "<osv.ExtendedLeaf: ('discontinued', '=', False) on product_product (ctx: )>"
Edited by Pelayo García