insertAll leaves inconsistent state with one entity inserted after the second entity fails on Hibernate

[njr-11]

Entity o5 is already inserted. Entity o7 is not. The test attempts the following and expects an EntityExistsException (due to o5),

                    orders.insertAll(List.of(o7, o5));

However, entity o7 appears to be inserted anyway, as indicated by a later attempt at inserting entity o7 which fails,

        List<PurchaseOrder> inserted = orders.insertAll(List.of(o7, o8));

see DataJPATestServlet.testEntitiesAsParameters