docs: protected Cron4jJob createCron4jJob(LaJobKey jobKey, JobSubIdentityAttr subIdentityAttr, List<LaJobKey> triggeringJobKeyList,
              OptionalThing<String> cron4jId, Cron4jTask cron4jTask) {
          final Cron4jJob job = newCron4jJob(jobKey, subIdentityAttr.getJobNote(), subIdentityAttr.getJobUnique(),
                  cron4jId.map(id -> Cron4jId.of(id)), cron4jTask, this);
          triggeringJobKeyList.forEach(triggeringJobKey -> {
              findJobByKey(triggeringJobKey).alwaysPresent(triggeringJob -> {
                  triggeringJob.registerNext(jobKey);
              });
          });
          return job;
      }