Fix rabbitmq prechecks broken due to Ansible upgrade

In Ansible 2.3.0 when statements should not include jinja2 templating
delimiters such as {{ }} or {% %}, and gate is broken with Ansible 2.3.1.

This patchset rewrite when statement in rabbitmq precheck task to not use
string interpolation.

Change-Id: Ie2f1666cc8ced7cf20ceba40c7c7aaec750778f9
Closes-Bug: #1695111

ansible/roles/rabbitmq/tasks/precheck.yml

@@ -58,4 +58,4 @@
 - fail: msg="Hostname has to resolve to IP address of api_interface"
   with_items: "{{ rabbitmq_hostnames.results }}"
   when:
-    - "'{{ hostvars[item['item']]['ansible_' + hostvars[item['item']]['api_interface']]['ipv4']['address'] }}' not in '{{ item.stdout }}'"
+    - "item.stdout.find(hostvars[item['item']]['ansible_' ~ hostvars[item['item']]['api_interface']]['ipv4']['address']) == -1"