Add tests for Jakarta EE integration of Jakarta Persistence with the CDI bean manager

[scottmarlow]

Add tests for jakartaee/platform#746

[edburns]

Notes from Platform call

• Stateless session beans have always been challenging to test robustly.
  • JPA 2.1 clarification: when you use EntityManager outside of a transaction, after each entity call, the PersistenceContext state is not preserved.

[scottmarlow]

Notes from Platform call

* Stateless session beans have always been challenging to test robustly.
  
  * JPA 2.1 clarification: when you use `EntityManager` outside of a transaction, after each entity call, the `PersistenceContext` state is not preserved.

Unless a persistence unit hint (e.g. extension) like jboss.as.jpa.deferdetach is used to defer the clearing/close of the persistence context until the session bean call completes.

[edburns]

Depends on #1624 .