tracker looks in its directory tree for executable files
to make available as subcommands. Users expect to find subcommands
from tracker-miners package but that fails as they are in different
tree. We also cannot change the lookup path since tracker-miners
also depends on a library from tracker package.
Until we can break the dependency cycle on package level:
tracker -> tracker-miners -> tracker-sparql (tracker)
we need to work around it. I chose to set an environment
variable that overrides the subcommands lookup to a tree
symlinking files from both packages in GNOME NixOS module.
https://gitlab.gnome.org/GNOME/tracker/-/issues/341
Fixes: https://github.com/NixOS/nixpkgs/issues/153378
3c1b474e44