HHH-8363 ClassLoaderServiceImpl should be defined as Stoppable

- also fix problem with JpaIntegrator holding references to beanmanager

Conflicts:
	hibernate-core/src/main/java/org/hibernate/boot/registry/classloading/internal/ClassLoaderServiceImpl.java
	hibernate-core/src/main/java/org/hibernate/boot/registry/classloading/spi/ClassLoaderService.java
	hibernate-entitymanager/src/main/java/org/hibernate/jpa/event/spi/JpaIntegrator.java
HHH-8363 cleanup and formatting

Conflicts:
	hibernate-core/src/main/java/org/hibernate/boot/registry/classloading/internal/ClassLoaderServiceImpl.java
HHH-8363 destroy the parent ServiceRegistry and stop its provided

Conflicts:
	hibernate-core/src/main/java/org/hibernate/boot/registry/classloading/internal/ClassLoaderServiceImpl.java
	hibernate-core/src/main/java/org/hibernate/boot/registry/internal/BootstrapServiceRegistryImpl.java
	hibernate-core/src/test/java/org/hibernate/test/service/ClassLoaderServiceImplTest.java
HHH-8363 Some more mem leak fixes

Conflicts:
	hibernate-core/src/main/java/org/hibernate/boot/registry/classloading/internal/ClassLoaderServiceImpl.java
	hibernate-envers/src/main/java/org/hibernate/envers/configuration/spi/AuditConfiguration.java
	hibernate-envers/src/main/java/org/hibernate/envers/event/spi/EnversIntegrator.java
HHH-8363 SessionFactoryServiceRegistryImpl should not call
parent#destroy, test failures, formatting

Conflicts:
	hibernate-core/src/main/java/org/hibernate/boot/registry/classloading/internal/ClassLoaderServiceImpl.java
	hibernate-core/src/main/java/org/hibernate/boot/registry/internal/StandardServiceRegistryImpl.java
	hibernate-core/src/test/java/org/hibernate/test/service/ClassLoaderServiceImplTest.java
	hibernate-envers/src/main/java/org/hibernate/envers/configuration/spi/AuditConfiguration.java
HHH-8502 - EnversIntegrator#disintegrate needs to check config for null

Conflicts:
	hibernate-envers/src/main/java/org/hibernate/envers/event/spi/EnversIntegrator.java