tasks: add run_ssh_cmd
    
    Paramiko is not compatible with FIPS.
    A replacement is needed, and since what clients use is "ssh",
    create a shim over it so that tests can leverage it.
    
    Fixes: https://pagure.io/freeipa/issue/8129
    Signed-off-by: François Cami <fcami@redhat.com>
    Reviewed-By: Mohammad Rizwan <myusuf@redhat.com>
    Reviewed-By: Michal Polovka <mpolovka@redhat.com>