Git commits in Moodle 3.9.0 by Anthony Forth

commit bcc3a463f68baf8f3f3feae883d05342fdddaa4c
Author: Anthony Forth <a.j.forth@open.ac.uk>
Date:   Wed, 12 Feb 2020 20:26:16 +0800
Tag:    v3.9.0-beta

MDL-67945 enrol: missing $DB in edit_instance_form