[FIX] stock: allow unlinking records in uninstall mode

Business cases should not prevent the unlink of module-related records
during an uninstall.

This commit allows the reinstallation of sale_stock with demo data and
also allows the proper removal of tables and records if a db has any
non-draft inventory adjustments.

closes odoo/odoo#39764

Signed-off-by: Adrian Torres (adt) <adt@odoo.com>