Git commits in Moodle 3.8.9 by Adam Olley

commit 7ec37a051e7188d7e20ac481e5686bd8aea77603
Author: Adam Olley <adam.olley@openlms.net>
Date:   Fri, 16 Apr 2021 12:28:28 +0800
Tag:    v3.8.9

MDL-70622 mod_lti: Prevent xss on lti 1.3 authentication script