ui: dc/ACME: fix not refreshing api column

When using a diffstore, we have to specify all fields that are
displayed, otherwise the store does not know which fields to check for
change

for the acme plugin view, 'api' was missing

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>

www/manager6/dc/ACMEClusterView.js

@@ -10,7 +10,7 @@ Ext.define('pve-acme-accounts', {
 
 Ext.define('pve-acme-plugins', {
     extend: 'Ext.data.Model',
-    fields: ['type', 'plugin'],
+    fields: ['type', 'plugin', 'api'],
     proxy: {
 	type: 'proxmox',
 	url: "/api2/json/cluster/acme/plugins",