Change ansiblehost role to rerun every 12 hours instead of 24

This renews certs at about the requested rate
Hopefully it doesn't break anything. I'm using LTS instances so it should be fine but you never know

roles/ansiblehost/tasks/main.yml

@@ -46,7 +46,8 @@
       dest: /opt/ansible-repo
   - name: Set up pull and run cronjob
     cron:
-      hour: "0"
+      minute: "0"
+      hour: "*/12"
       name: ansible-pull
       job: "cd /opt/ansible-repo && ansible-playbook ec2.yml > /var/log/ansible-pull.log 2>&1"
   become: true