[FIX] sale: fix custom values order in product description

STEPS:
* activate Product Configurator
* create 3 attributes with custom values option
* create a quotation with a product having all 3 attributes and custom values
* select the custom values for attributes in different orders for each SO line

BEFORE: Product description get random order for the custom attributes list

AFTER: Order is fine

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opw-2379778

closes odoo/odoo#61836

Signed-off-by: Ivan Yelizariev // IEL <yelizariev@users.noreply.github.com>