CVE-2020-25631

A vulnerability was found in Moodle 3.9 to 3.9.1, 3.8 to 3.8.4 and 3.7 to 3.7.7 where it was possible to include JavaScript in a book's chapter title, which was not escaped on the "Add new chapter" page. This is fixed in 3.9.2, 3.8.5 and 3.7.8.