Update hosts/docker/configuration.nix

added systemd job to prune docker data

hosts/docker/configuration.nix

@@ -119,6 +119,25 @@ systemd.timers.nextcloud = {
   };
 };
 
+# Create nextcloud cron scheduled task
+systemd.services.docker-prune = {
+  description = "Prune docker data";
+  script = ''${pkgs.docker} system prune --volumes --all'';
+  serviceConfig = {
+    Type = "oneshot";
+    User = "nixos";
+  };
+  path = with pkgs; [ docker docker-compose ];
+};
+
+systemd.timers.docker-prune = {
+  wantedBy = [ "timers.target" ];
+  timerConfig = {
+    OnCalendar = "monthly";
+    Persistent = true;
+  };
+};
+    
 # create update task
 
 #  systemd.services.update-containers = {