Add require_login() to proxy_pluginfile.php

Author: Fragonite

proxy_pluginfile.php

@@ -23,6 +23,7 @@
  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 
+require_login();
 require_once(dirname(__FILE__) . '/../../config.php');
 require_once($CFG->libdir . '/filelib.php');
 \core\session\manager::write_close();