[FIX] sale_timesheet: sale order line of subtasks
[FIX] sale_timesheet: sale order line of subtasks

We want to set the sale line of the parent when changing the subtasks parent
but not force changing it when modifying the SO line of the parent task, and
we have to reset (empty) so line on subtasks when changing the customer of a
task to avoid no seeing the current SO line in its domain (dropdown) since the
customer has changed.

Task #34703

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