docs: private PersistenceServiceUnit createPsu(int jobInstanceVersion, int jobExecutionVersion) throws Exception {
          return databaseStore.createPersistenceServiceUnit(getJobInstanceEntityClass(jobInstanceVersion).getClassLoader(),
                                                            getJobExecutionEntityClass(jobExecutionVersion).getName(),
                                                            getJobInstanceEntityClass(jobInstanceVersion).getName(),
                                                            StepThreadExecutionEntity.class.getName(),
                                                            StepThreadInstanceEntity.class.getName(),
                                                            TopLevelStepExecutionEntity.class.getName(),
                                                            TopLevelStepInstanceEntity.class.getName());
      }