PHP Notice: Undefined index: success

Hello,

Just to let you know that I recently have a PHP notice with the plugin.

Here is the backtrace:

PHP Notice: Undefined index: success

1. do_action('admin_menu')
wp-admin/includes/menu.php:154
2. rsssl_admin->rsssl_edit_admin_menu()
wp-includes/class-wp-hook.php:286
3. rsssl_admin->count_plusones()
wp-content/plugins/really-simple-ssl/class-admin.php:2391
wp-content/plugins/really-simple-ssl/class-admin.php:2697

Thanks, and keep up the great work ??

Regards.