Support for JPA 4.0 package and module descriptor discovery

As mentioned in #37315, JPA 4.0 M7 introduces dedicated `PersistenceUnitInfo` callbacks for package and module descriptor discovery, as well as corresponding declarative elements in `persistence.xml`. We intend to support those in Spring Framework 7.1 as part of our optional JPA 4.0 support, discovering annotated `module-info` classes next to `package-info` and exposing those through the JPA 4.0 M7 SPI.