ce9346e ipatests: use dnf download to download pkgs

Authored and Committed by frenaud a year ago
    ipatests: use dnf download to download pkgs
    
    The tasks.download_packages method is using
    dnf install --downloaddir PATH --downloadonly
    but the option --downloaddir does not exist any more with
    dnf5 that is shipped in rawhide.
    
    An alternative is to use
    dnf download
    which downloads to the current directory. This alternative
    works for both dnf and dnf5.
    
    Fixes: https://pagure.io/freeipa/issue/9399
    
    Signed-off-by: Florence Blanc-Renaud <flo@redhat.com>
    Reviewed-By: Rob Crittenden <rcritten@redhat.com>