[FIX] sale_mrp: allow production without finished products
[FIX] sale_mrp: allow production without finished products

Have a mrp.production that you cancel, and delete the finished products lines

Before this commit, the computation of the sale_name crashed because we did
an index selection on an empty recordset

After this commit, there is no crash

opw 1851217
closes #24923

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