Fix empty list comparison throwing valueerror

tasks/plugins.yml

@@ -25,7 +25,7 @@
     shell: umask 0022; sensu-install -p {{ item }}
     with_items: "{{ sensu_remote_plugins }}"
     changed_when: false
-    when: sensu_remote_plugins > 0
+    when: sensu_remote_plugins | length > 0
 
   - name: Register available checks
     local_action: command ls {{ static_data_store }}/sensu/checks