Git commits in Moodle 3.7.5 by Colin Campbell

commit c0cf6abf34ce96b132e70ca278db9f147eee0c50
Author: Colin Campbell <colin@umn.edu>
Date:   Thu, 10 Oct 2019 09:38:25 +0800
Tag:    v3.7.5

MDL-52189 file: skip deleting temp files that appear during cleanup