Add whonix-config package back

[deeplow]

Partially reverts d5fdbb4 and d175066 in order to restore the whonix-config package. This will be fully removed in a future release 1 but for now it will be kept, should there be any need to re-enable it.

This is mandatory, given that in its current form, the workstation changes meant to accompany this release do not remove sd-whonix nor its salt states. This means that the package whonix-config is still expected to exist.

Test plan

1. Deploy with workstation before the merging of Prepares path for sd-whonix whonix removal securedrop-workstation#1414
2. Install securedrop-proxy-0.16.0 in sd-small-bookworm-template, shut down template and restart sd-proxy.
3. Install built whonix-config package in whonix-gateway-17
4. Client is able to connect to server

Checklist

This change accounts for:

• testing changes on Qubes as needed (especially changes related to cryptography, export, disposable VM use, or complex UI changes)
• any needed updates to the AppArmor profile for files beyond the application code
• any needed self-contained database migrations (including testing against a clean test database from main)

[legoktm]

Per standup today, we're going to close this for now, and just keep it in our back pocket in case we do need to do a revert. The old packages will still be on apt.freedom.press in case we do need them.

[deeplow]

The old packages will still be on apt.freedom.press in case we do need them.

Perfect. New workstations will still install this package, but if it's available, then that should not be a problem.