fix linter errors

roles/grafana/tasks/plugins.yml

@@ -1,7 +1,7 @@
 ---
 - name: "Create plugin directory"
   ansible.builtin.file:
-    path: "{{ plugins_dir }}"
+    path: "{{ grafana_plugins_dir }}"
     state: directory
     owner: "{{ grafana_user }}"
     group: "{{ grafana_group }}"
@@ -11,6 +11,6 @@
   community.grafana.grafana_plugin:
     name: "{{ plugin.name }}"
     version: "{{ plugin.version }}"
-    grafana_plugins_dir: "{{ plugins_dir }}"
+    grafana_plugins_dir: "{{ grafana_plugins_dir }}"
     state: "{{ plugin.state | default('present') }}"
   notify: "(Re)start and enable Grafana"