gnome-desktop: fix thumbnail generation on musl systems.
/etc/ld.so.cache doesn't exist on musl systems, which makes the bwrap
command fail. Users will have to remove the "failed generation" cache
from ~/.cache/thumbnails/fail/ for nautilus to reattempt thumbnail
generation of previously visited directories.
Upstream issue:
https://gitlab.gnome.org/GNOME/gnome-desktop/-/issues/117
Seems to be the direction upstream is moving in as well:
https://gitlab.gnome.org/GNOME/gnome-desktop/-/merge_requests/107
Fixes #29767.
23c6e2e53a