Jpa store tests fail with hibernate 5.1

Some tests from infinispan-cache-store are failing because this change https://github.com/infinispan/infinispan/commit/602fb0aa055ec4b1d382fbbe4886922d12538767

That line was changed from HibernateEntityManagerFactory to SessionFactoryImpl when upgraded to Hibernate ORM 5.2.7.Final

EAP 7.1 uses hibernate 5.1, so it's important to fix that