[release-v1.8] vsp: Only remove confirmed payments

The only way to be certain a VSP has acknowledged a fee tx and added a
ticket to its voting wallets is to check FeeTxStatus == "confirmed".
Checking for 6 confirmations on the fee tx is not an adequate
substitute.

For example, if a client has broadcast it's own fee tx rather than
waiting for the VSP to do it, it's possible that the tx could be mined
and have 6+ confs, but the amount paid is not enough, or the payment is
sent to the wrong address.

Backport of 3c8cd47

internal/vsp/feepayment.go

@@ -865,31 +865,7 @@ func (fp *feePayment) confirmPayment() (err error) {
 
 	status, err := fp.client.status(ctx, &fp.ticketHash)
 	if err != nil {
-
 		log.Warnf("Rescheduling status check for %v: %v", &fp.ticketHash, err)
-
-		// Stop processing if the status check cannot be performed, but
-		// a significant amount of confirmations are observed on the fee
-		// transaction.
-		//
-		// Otherwise, chedule another confirmation check, in case the
-		// status API can be performed at a later time or more
-		// confirmations are observed.
-		fp.mu.Lock()
-		feeHash := fp.feeHash
-		fp.mu.Unlock()
-		confs, err := w.TxConfirms(ctx, &feeHash)
-		if err != nil {
-			return err
-		}
-		if confs >= 6 {
-			fp.remove("confirmed")
-			err = w.UpdateVspTicketFeeToConfirmed(ctx, &fp.ticketHash, &feeHash, fp.client.URL, fp.client.PubKey)
-			if err != nil {
-				return err
-			}
-			return nil
-		}
 		fp.schedule("confirm payment", fp.confirmPayment)
 		return nil
 	}