Remove unused parameter

[RSpeekenbrink]

Remove unused amount parameter in CompletePurchaseRequest. Validation on this parameter means you have to access your order before you can actually access the PaymentId trough a gateway meaning you have to add custom logic for buckaroo payments. IE:

$order = Order::find($request->get('BQ_INVOICENUMBER'));
$response = Omnipay::CompletePurchase(array_merge(
    [ 'amount' => $order->amount ],
    request()->all(),
))->send();

With this fix this is no longer required.