[FIX] website_sale: optional product quantity
[FIX] website_sale: optional product quantity

When incrementing the quantity of a product in the cart, the optional
products linked to this product must be incremented too.

opw:653351

sysadminmatmoz/OCB,dfang/odoo,stephen144/odoo,laslabs/odoo,Elico-Corp/odoo_OCB,Elico-Corp/odoo_OCB,bplancher/odoo,bplancher/odoo,Elico-Corp/odoo_OCB,microcom/odoo,ygol/odoo,storm-computers/odoo,sysadminmatmoz/OCB,storm-computers/odoo,stephen144/odoo,ygol/odoo,microcom/odoo,optima-ict/odoo,sysadminmatmoz/OCB,optima-ict/odoo,ygol/odoo,optima-ict/odoo,bplancher/odoo,ygol/odoo,stephen144/odoo,laslabs/odoo,sysadminmatmoz/OCB,microcom/odoo,Elico-Corp/odoo_OCB,ygol/odoo,hip-odoo/odoo,microcom/odoo,stephen144/odoo,optima-ict/odoo,storm-computers/odoo,dfang/odoo,sysadminmatmoz/OCB,dfang/odoo,stephen144/odoo,bplancher/odoo,laslabs/odoo,Elico-Corp/odoo_OCB,bplancher/odoo,hip-odoo/odoo,sysadminmatmoz/OCB,hip-odoo/odoo,laslabs/odoo,ygol/odoo,Elico-Corp/odoo_OCB,dfang/odoo,optima-ict/odoo,storm-computers/odoo,laslabs/odoo,stephen144/odoo,laslabs/odoo,hip-odoo/odoo,optima-ict/odoo,bplancher/odoo,dfang/odoo,sysadminmatmoz/OCB,microcom/odoo,dfang/odoo,hip-odoo/odoo,ygol/odoo,microcom/odoo,hip-odoo/odoo,storm-computers/odoo,storm-computers/odoo