conduit: Switch to stable package since that has updated

configuration/services/conduit.nix

@@ -2,7 +2,6 @@
   pkgs,
   config,
   lib,
-  flake-inputs,
   ...
 }: let
   inherit (lib.strings) concatMapStringsSep;
@@ -13,7 +12,6 @@
 in {
   services.matrix-conduit = {
     enable = true;
-    package = flake-inputs.nixpkgs-unstable.legacyPackages.${pkgs.system}.matrix-conduit;
     settings.global = {
       address = "127.0.0.1";
       server_name = domain;