Sort the results

Results need to be sorted.  OpenSource Chef 11 doesn't preserve order.

Change-Id: I00e649f1833915f6372d7d59dcefc6c073aca29f

recipes/rabbitmq-server.rb

@@ -46,7 +46,7 @@ if node["openstack"]["mq"]["cluster"]
   qs = "roles:#{rabbit_server_role} AND chef_environment:#{node.chef_environment}"
   node.override["rabbitmq"]["cluster_disk_nodes"] = search(:node, qs).map do |n|
     "#{user}@#{n['hostname']}"
-  end
+  end.sort
 end
 
 include_recipe "rabbitmq"

spec/rabbitmq-server_spec.rb

@@ -36,7 +36,7 @@ describe "openstack-ops-messaging::rabbitmq-server" do
         )
       end
 
-      it "overrides cluster_disk_nodes" do
+      it "overrides and sorts cluster_disk_nodes" do
         expect(@chef_run.node['rabbitmq']['cluster_disk_nodes']).to eql(
           ["guest@host1", "guest@host2"]
         )

spec/spec_helper.rb

@@ -19,8 +19,8 @@ def ops_messaging_stubs
   ::Chef::Recipe.any_instance.stub(:search).
     with(:node, "roles:os-ops-messaging AND chef_environment:_default").
     and_return [
-      { 'hostname' => 'host1' },
-      { 'hostname' => 'host2' }
+      { 'hostname' => 'host2' },
+      { 'hostname' => 'host1' }
     ]
   ::Chef::Recipe.any_instance.stub(:user_password).
     and_return "rabbit-pass"