[FIX] mrp: working hours required
[FIX] mrp: working hours required

Mrp workcenters have a resource_calendar_id to specifie its working
hours. On the form view, this field is optionnal but is mandatory in the
form view.

This commit set it as required in the view to avoid the classical 'object
with reference * - *' error.

Task : 1876847

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