code: @JsonIgnore
      protected boolean isRefreshTokenExpired(final TicketState ticketState) {
          if (ticketState == null) {
              return true;
          }
          val expiringTime = ticketState.getCreationTime().plus(this.timeToKillInSeconds, ChronoUnit.SECONDS);
          return expiringTime.isBefore(ZonedDateTime.now(ZoneOffset.UTC));
      }
docs: Is refresh token expired ?
  
  @param ticketState the ticket state
  @return the boolean