[FIX] core: read model from field in `field_compute`
[FIX] core: read model from field in `field_compute`

Oversight of "simple refactoring" in 634775bff6d9eba9d4548cc801071a942895a719

closes odoo/odoo#51158

X-original-commit: 046b0dedda8f43e4ae13958a34a446e8a73c8d3f
Signed-off-by: Raphael Collet (rco) <fcee45b878db1f337818c5c606c1542797080a40@openerp.com>

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