Fix issues for phpdoc check

Get rid of ci for moodle 37,38

auth.php

@@ -58,7 +58,6 @@ class auth_plugin_outage extends auth_plugin_base {
     /**
      * Always returns false (password wrong or user does not exist).
      *
-     * @inheritdoc PHPMD will not warn about unused parameters if overriding.
      * @param string $username Not used in this plugin.
      * @param string $password Not used in this plugin.
      * @return bool False