Git commits in Moodle 3.7.7 by Matteo Scaramuccia

commit a4d4a0b2807251650b51adbac8dc9f5b87ce6750
Author: Matteo Scaramuccia <moodle@matteoscaramuccia.com>
Date:   Thu, 11 Jun 2020 04:44:07 +0800
Tag:    v3.7.7

MDL-66322 travis: Configure a local copy of 'exttests'