[FIX] delivery: missing parenthesis
[FIX] delivery: missing parenthesis

Thanks to @xmo-odoo and its Python3 virtual machine for spotting this
one (and shame on Python2 that does not crash when comparing a method to
a float because voilà).

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