multi: formatting and comment fixes

zpay32/invoice_test.go

@@ -951,7 +951,6 @@ func TestInvoiceChecksumMalleability(t *testing.T) {
 	if err == nil {
 		t.Fatalf("Did not get expected error when decoding invoice")
 	}
-
 }
 
 func compareInvoices(expected, actual *Invoice) error {