HHH-19348 Change scope of private methods in AbstractSharedSessionContract

Change scopes of some private methods to avoid duplication in Hibernate Reactive.

Related to hibernate/hibernate-reactive#2181

Author: DavideD

hibernate-core/src/main/java/org/hibernate/internal/AbstractSharedSessionContract.java

@@ -977,15 +977,18 @@ private <T> NativeQueryImplementor<T> buildNativeQuery(String sql, @Nullable Cla
 		}
 	}
 
-	final EntityPersister requireEntityPersister(Class<?> entityClass) {
+	// Hibernate Reactive may need to use this
+	protected final EntityPersister requireEntityPersister(Class<?> entityClass) {
 		return getMappingMetamodel().getEntityDescriptor( entityClass );
 	}
 
-	final EntityPersister requireEntityPersister(String entityName) {
+	// Hibernate Reactive may need to use this
+	protected final EntityPersister requireEntityPersister(String entityName) {
 		return getMappingMetamodel().getEntityDescriptor( entityName );
 	}
 
-	final CollectionPersister requireCollectionPersister(String roleName) {
+	// Hibernate Reactive may need to use this
+	protected final CollectionPersister requireCollectionPersister(String roleName) {
 		return getMappingMetamodel().getCollectionDescriptor( roleName );
 	}