added clustername to .kitchen.yml
added clustername to .kitchen.yml

Eurotherm/chef-elasticsearch-cluster,Eurotherm/chef-elasticsearch-cluster,vkhatri/chef-elasticsearch-cluster,Eurotherm/chef-elasticsearch-cluster,vkhatri/chef-elasticsearch-cluster,shortdudey123/chef-elasticsearch-cluster,shortdudey123/chef-elasticsearch-cluster,vkhatri/chef-elasticsearch-cluster,shortdudey123/chef-elasticsearch-cluster