Add video/vnd.avi mime type
shared-mime-info
changed the mime type for AVI videos from video/x-msvideo
to video/vnd.avi
: https://gitlab.freedesktop.org/xdg/shared-mime-info/-/commit/02741a47ae6bc8e3f335e37806d9abcd8db341f3
See also https://discourse.gnome.org/t/thumbnail-avi-files/17608