[FIX] translate: fix test on lxml node
[FIX] translate: fix test on lxml node

Specifically, replace `not node.getparent()` by `node.getparent() is None`.

hip-odoo/odoo,ygol/odoo,dfang/odoo,hip-odoo/odoo,ygol/odoo,dfang/odoo,ygol/odoo,dfang/odoo,hip-odoo/odoo,hip-odoo/odoo,dfang/odoo,ygol/odoo,hip-odoo/odoo,dfang/odoo,ygol/odoo,ygol/odoo,ygol/odoo,hip-odoo/odoo,dfang/odoo