docs: public String getNextDay(String dateString, boolean onlyBusinessDays) {
          DateTimeFormatter parser = ISODateTimeFormat.date();
          DateTime date = parser.parseDateTime(dateString).plusDays(1);
          Calendar cal = Calendar.getInstance();
          cal.setTime(date.toDate());
  
          if (onlyBusinessDays) {
              if (cal.get(Calendar.DAY_OF_WEEK) == 1 || cal.get(Calendar.DAY_OF_WEEK) == 7
                  || isHoliday(date.toString().substring(0, 10))) {
                  return getNextDay(date.toString().substring(0, 10), true);
              } else {
                  return parser.print(date);
              }
          } else {
              return parser.print(date);
          }
      }