I ran into this error when trying to run `opendkim-genkey` in a vars
generator:
```console
=========================================================================== Command ===========================================================================
nix \
--extra-experimental-features 'nix-command flakes' \
shell \
--inputs-from /nix/store/9r3ddw80dz4qzci9pj57ppbh6gy2pgv9-clan-cli/lib/python3.12/site-packages/clan_cli/nixpkgs \
'nixpkgs#bash' \
'nixpkgs#bubblewrap' \
-c bwrap \
--unshare-all --tmpfs \
/ \
--ro-bind /nix/store \
/nix/store \
--dev /dev \
--bind /tmp/nix-shell.ClOjgJ/vars-kh4qrnas \
/tmp/nix-shell.ClOjgJ/vars-kh4qrnas \
--chdir / \
--bind /proc \
/proc \
--uid 1000 \
--gid 1000 \
-- bash \
-c /nix/store/p0089w4y1w3h535g7ipv4jl4r6mb2hs2-generator-dkim-playground.jflei.com.mail
=========================================================================== Stderr ============================================================================
perl: warning: Setting locale failed.
perl: warning: Please check that your locale settings:
LANGUAGE = (unset),
LC_ALL = (unset),
LC_CTYPE = (unset),
LC_NUMERIC = (unset),
LC_COLLATE = (unset),
LC_TIME = (unset),
LC_MESSAGES = (unset),
LC_MONETARY = (unset),
LC_ADDRESS = (unset),
LC_IDENTIFICATION = (unset),
LC_MEASUREMENT = (unset),
LC_PAPER = (unset),
LC_TELEPHONE = (unset),
LC_NAME = (unset),
LANG = "en_US.UTF-8"
are supported and installed on your system.
perl: warning: Falling back to the standard locale ("C").
Can't exec "/bin/sh": No such file or directory at /nix/store/nfawbww80p1hgpymfgq1vq8wqlak75yh-opendkim-2.11.0-Beta2/sbin/.opendkim-genkey-wrapped line 139.
.opendkim-genkey-wrapped: openssl died with signal %d
127
Return Code: 1
1 hosts failed with an error. Check the logs above
```
As we allow `/bin/sh` in the nix build sandbox, I assume we're OK
allowing it here as well?
On macOS mktemp returns a temporary directory in a symlink.
Nix has a bug where it won't accept path:// located in a symlink.
This avoid this issue by always resolving symlinks as returned by
TemporaryDirectory.
Prior to this, when initializing new machines, only the current user had access to it's key which prevents other admin users to deploy this machine later
Migrating generated files from the facts subsystem to the vars subsystem is now possible.
HowTo:
1. declare `clan.core.vars.generators.<generator>.migrateFact = my_service` where `my_service` refers to a service from `clan.core.facts.services`
2. run `clan vers generate your_machine` or `clan machines update your_machine`
Vars will only be migrated for a generator if:
1. The facts service specified via `migrateFact` does exist
2. None of the vars to generate exist yet
3. All public var names exist in the public facts store
4. All secret var names exist in the secret fact store
If the migration is deemed possible, the generator script will not be executed. Instead the files from the public or secret facts store are read and stored into the corresponding vars store