Remove response method in support file
Remove response method in support file

This shadow's rspec `response` in test bodies.

freerunningtech/solidus-adyen,freerunningtech/solidus-adyen,StemboltHQ/solidus-adyen,StemboltHQ/solidus-adyen,StemboltHQ/solidus-adyen,freerunningtech/solidus-adyen,freerunningtech/solidus-adyen,StemboltHQ/solidus-adyen