Ticket - 49562 integrate changelog database to main database
    
    Bug description:
    	PHASE 2 of backend redesign:
    	http://www.port389.org/docs/389ds/design/integrate-changelog-database-and-backend-database.html
            Mainly changelog managed its own access to the database and it uses a global
            config entry (cn=changelog5,cn=config) not related to the backend/replica.
    
    Fix description:
    	The fix is described in the design.
            Plus:
             - use-after-free (remove+add replica, set)
             - various leaks (triggered with CI tests fixup-tombstone, cascading)
    	 - Plus some changes in the CI tests
    
    https://pagure.io/389-ds-base/issue/49562
    
    Reviewed by: Mark Reynolds, William Brown, Thierry Bordaz