Use expanduser instead of HOME env var
    
    The HOME directory may not be available in containers. It's also the
    wrong variable on some platforms. Use os.path.expanduser() instead of
    HOME.
    
    Fixes: https://pagure.io/freeipa/issue/7837
    Signed-off-by: Christian Heimes <cheimes@redhat.com>
    Reviewed-By: Alexander Bokovoy <abokovoy@redhat.com>