[FIX] mrp: do not rename warehouse when changing code
[FIX] mrp: do not rename warehouse when changing code

If only the code of a warehouse is changed, `name` is None.
Do not try to set None as the new pull name.

Fixes #14766

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