change setup known_host to all nodes

roles/setupKnownHosts/tasks/main.yml

 - name: "Templating /etc/ssh/known_hosts"
   template: src=known_hosts.j2 dest=/etc/ssh/known_hosts owner=root group=root mode=600
-  delegate_to: "{{ slurmlogin }}"
   sudo: true
   register: sshknowhost