feat(backup): set backup roles to admin(remove oper)

modules/backup/client/config/admin/backup-admin.client.menu.js

@@ -13,6 +13,7 @@
       title: 'MENU_ADMIN_BACKUP',
       state: 'admin.backup',
       position: 50,
+      roles: ['admin'],
       divider: true
     });
   }

modules/backup/server/policies/backup.server.policy.js

@@ -15,7 +15,7 @@ exports.invokeRolesPolicies = function () {
   acl.allow(
     [
       {
-        roles: ['admin', 'oper'],
+        roles: ['admin'],
         allows: [
           {resources: '/api/backup', permissions: '*'},
           {resources: '/api/backup/:filename', permissions: '*'}