Issue 49761 - Fix test suite issues
    
    Description: A lot of tests are failing because of the API changes.
    We need to fix them ASAP.
    
    Fix description: Add __init__.py to import and mapping_tree test suite
    so it will create its own __pycache__.
    Use the new Agriments object for reinit.
    Run range_search memory leak test only when ASAN is enabled and
    remove valgrind support because ASAN is enough.
    Generate ou=People and ou=Groups in the dbgen.py module, it is
    required by some tests.
    In the replica.py module, use existing credentials when we join master to
    the existing first_master and  when we failed to get it from the ReplicationManager.
    
    https://pagure.io/389-ds-base/issue/49761
    
    Reviewed by: mreynolds (Thanks!)