Git commits in Moodle 3.11.3 by Huong Nguyen

commit 3a42d256afc049eb76dcc20447333cb3350eeb9d
Author: Huong Nguyen <huongnv13@gmail.com>
Date:   Thu, 09 Sep 2021 10:33:15 +0800
Tag:    v3.11.3

MDL-71899 performance: Improve activity completion data caching


commit 604d58ff4a4424c2106448dab66b4bd5525ca641
Author: Huong Nguyen <huongnv13@gmail.com>
Date:   Thu, 09 Sep 2021 10:21:11 +0800
Tag:    v3.11.3

MDL-71899 performance: Improve course image caching


commit 298951cd2efe520b886d3a81b185a6f89739fdcf
Author: Huong Nguyen <huongnv13@gmail.com>
Date:   Sun, 01 Aug 2021 23:24:46 +0800
Tag:    v3.11.3

MDL-71797 quiz: Improve the checks when fetching user's attempts


commit f53dd9c5d2dd7fa75668e0086d89c702c569fb3b
Author: Huong Nguyen <huongnv13@gmail.com>
Date:   Wed, 07 Jul 2021 10:27:35 +0800
Tag:    v3.11.3

MDL-71656 atto: Add meaningful labels to colour items