[FIX] website_slides: slide sorting
[FIX] website_slides: slide sorting

Ensure deterministic sorting for slides with the same sequence.

opw-2283154

closes odoo/odoo#54007

X-original-commit: 46bd51dc5f7b674409beac2557cbd19ec001944b
Signed-off-by: Nicolas Martinelli (nim) <771435c469f83f6aa9c405ac5e1ed06314a94f2d@odoo.com>

ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo