Cannot delete definitively a course with a portfolio

08:53:00,797  WARN SqlExceptionHelper:129 - SQL Error: 0, SQLState: 23503
08:53:00,797 ERROR SqlExceptionHelper:131 - ERROR: update or delete on table "o_repositoryentry" violates foreign key constraint "pf_binder_course_idx" on table "o_pf_binder"
  Detail: Key (repositoryentry_id)=(1095008258) is still referenced from table "o_pf_binder".
08:53:00,800  INFO AbstractBatchImpl:193 - HHH000010: On release of batch it still contained JDBC statements
08:53:00,802 ERROR ExceptionMapperStandardImpl:39 - HHH000346: Error during managed flush [org.hibernate.exception.ConstraintViolationException: could not execute statement]
08:53:00,803  WARN DBImpl:203 - Caught Exception in DBImpl.commit.
>>>stack of 1.cause::javax.persistence.RollbackException: Error while committing the transaction
-> at org.hibernate.internal.ExceptionConverterImpl.convertCommitException(ExceptionConverterImpl.java:75)
   at org.hibernate.engine.transaction.internal.TransactionImpl.commit(TransactionImpl.java:71)
   at org.olat.core.commons.persistence.DBImpl.commit(DBImpl.java:713)
   at org.olat.repository.manager.RepositoryServiceImpl.deleteRepositoryEntryAndBaseGroups(RepositoryServiceImpl.java:469)
   at org.olat.repository.manager.RepositoryServiceImpl.deletePermanently(RepositoryServiceImpl.java:440)
   at org.olat.repository.ui.author.ConfirmDeletePermanentlyController.deleteEntries(ConfirmDeletePermanentlyController.java:293)
   at org.olat.repository.ui.author.ConfirmDeletePermanentlyController.doCompleteDelete(ConfirmDeletePermanentlyController.java:240)
   at org.olat.repository.ui.author.ConfirmDeletePermanentlyController.formInnerEvent(ConfirmDeletePermanentlyController.java:211)
   at org.olat.core.gui.components.form.flexible.impl.FormBasicController.event(FormBasicController.java:421)
   at org.olat.core.gui.control.DefaultController.dispatchEvent(DefaultController.java:202)
   at org.olat.core.gui.components.AbstractComponent$1.run(AbstractComponent.java:240)
>>>stack of 2.cause::javax.persistence.PersistenceException: org.hibernate.exception.ConstraintViolationException: could not execute statement
-> at org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:147)
   at org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:155)
   at org.hibernate.internal.ExceptionConverterImpl.convertCommitException(ExceptionConverterImpl.java:56)
   at org.hibernate.engine.transaction.internal.TransactionImpl.commit(TransactionImpl.java:71)
   at org.olat.core.commons.persistence.DBImpl.commit(DBImpl.java:713)
   at org.olat.repository.manager.RepositoryServiceImpl.deleteRepositoryEntryAndBaseGroups(RepositoryServiceImpl.java:469)
   at org.olat.repository.manager.RepositoryServiceImpl.deletePermanently(RepositoryServiceImpl.java:440)
   at org.olat.repository.ui.author.ConfirmDeletePermanentlyController.deleteEntries(ConfirmDeletePermanentlyController.java:293)
   at org.olat.repository.ui.author.ConfirmDeletePermanentlyController.doCompleteDelete(ConfirmDeletePermanentlyController.java:240)
   at org.olat.repository.ui.author.ConfirmDeletePermanentlyController.formInnerEvent(ConfirmDeletePermanentlyController.java:211)
   at org.olat.core.gui.components.form.flexible.impl.FormBasicController.event(FormBasicController.java:421)
>>>stack of 3.cause::org.hibernate.exception.ConstraintViolationException: could not execute statement
-> at org.hibernate.exception.internal.SQLStateConversionDelegate.convert(SQLStateConversionDelegate.java:112)
   at org.hibernate.exception.internal.StandardSQLExceptionConverter.convert(StandardSQLExceptionConverter.java:42)
   at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:111)
   at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:97)
   at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.executeUpdate(ResultSetReturnImpl.java:208)
   at org.hibernate.engine.jdbc.batch.internal.NonBatchingBatch.addToBatch(NonBatchingBatch.java:45)
   at org.hibernate.persister.entity.AbstractEntityPersister.delete(AbstractEntityPersister.java:3315)
   at org.hibernate.persister.entity.AbstractEntityPersister.delete(AbstractEntityPersister.java:3552)
   at org.hibernate.action.internal.EntityDeleteAction.execute(EntityDeleteAction.java:99)
   at org.hibernate.engine.spi.ActionQueue.executeActions(ActionQueue.java:589)
   at org.hibernate.engine.spi.ActionQueue.executeActions(ActionQueue.java:463)
>>>stack of 4.cause::org.postgresql.util.PSQLException: ERROR: update or delete on table "o_repositoryentry" violates foreign key constraint "pf_binder_course_idx" on table "o_pf_binder"