[FIX] pos_mercury: don't 'Wait for swipe' for negative payments
[FIX] pos_mercury: don't 'Wait for swipe' for negative payments

We don't support refunds this way. Instead these should be handled
separately through the Vantiv backend.

opw-805302

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