fix wrong path in include install_host.yml in etcd role (#5256)

roles/etcd/tasks/main.yml

@@ -81,7 +81,7 @@
   when: is_etcd_master
 
 - name: Install etcdctl binary from etcd role
-  include_tasks: "{{ role_path }}/../../etcd/tasks/install_host.yml"
+  include_tasks: install_host.yml
   vars:
     etcd_cluster_setup: true
   when: