Fix Grafana config for extra conf

Previous change[1] of config for grafana introduced
new bugs.

[1]https://review.openstack.org/#/c/548291/

Change-Id: Ib62f0670003612073ff08f702febe81c753b72e5

ansible/roles/grafana/tasks/config.yml

@@ -53,8 +53,6 @@
 
 - name: Copying over extra configuration file
   become: true
-  vars:
-    service_name: "{{ item.0 }}"
   template:
     src: "{{ item.path }}"
     dest: "{{ node_config_directory }}/grafana/{{ item.path | basename }}"

ansible/roles/grafana/templates/grafana.json.j2

@@ -12,7 +12,7 @@
             "source": "{{ container_config_directory }}/{{ plugin.path | basename }}",
             "dest": "/etc/grafana/{{ plugin.path | basename }}",
             "owner": "grafana",
-            "perm": "0600",
+            "perm": "0600"
         },
 {% endfor %}{% endif %}{% endif %}
         {