RabbitMQ conditional fix

Fixed conditional where a value could be tested that did not
exist because of the value in the conditional.

Duplicated the RabbitMQ cluster variable to prevent the conditional
test from failing from the playbook being resumed from a particular
point after the value is first collected.

Change-Id: I7e162c4dbdef8f2ae5e210a2aef6666e1e3e56b6