redshift: fix evaluation

Broken by 77d33f77d7cffa9e53c780398ae0fadc8dd0eda5 , cc @nckx

Changed files
+1 -1
nixos
modules
services
+1 -1
nixos/modules/services/x11/redshift.nix
···
-l ${cfg.latitude}:${cfg.longitude} \
-t ${toString cfg.temperature.day}:${toString cfg.temperature.night} \
-b ${toString cfg.brightness.day}:${toString cfg.brightness.night} \
-
${cfg.extraOptions}
+
${lib.strings.concatStringsSep " " cfg.extraOptions}
'';
environment = { DISPLAY = ":0"; };
serviceConfig.Restart = "always";