networking/nftables: ensure deletions

        RemainAfterExit = true;

        ExecStart = [ ensureDeletions rulesScript ];

        ExecStartPost = saveDeletionsScript;

        ExecReload = [ rulesScript saveDeletionsScript ];

        ExecReload = [ ensureDeletions rulesScript saveDeletionsScript ];

        ExecStop = [ deletionsScriptVar cleanupDeletionsScript ];

        StateDirectory = "nftables";

      };