treewide: remove redundant quotes

nixos/modules/services/security/fprot.nix

@@ -67,7 +67,7 @@ in {
 
     services.cron.systemCronJobs = [ "*/${toString cfg.updater.frequency} * * * * root start fprot-updater" ];
 
-    systemd.services."fprot-updater" = {
+    systemd.services.fprot-updater = {
       serviceConfig = {
         Type = "oneshot";
         RemainAfterExit = false;

nixos/modules/services/security/physlock.nix

@@ -99,7 +99,7 @@ in
       # for physlock -l and physlock -L
       environment.systemPackages = [ pkgs.physlock ];
 
-      systemd.services."physlock" = {
+      systemd.services.physlock = {
         enable = true;
         description = "Physlock";
         wantedBy = optional cfg.lockOn.suspend   "suspend.target"

nixos/modules/services/security/sks.nix

@@ -108,7 +108,7 @@ in {
       hkpAddress = "'" + (builtins.concatStringsSep " " cfg.hkpAddress) + "'" ;
       hkpPort = builtins.toString cfg.hkpPort;
     in {
-      "sks-db" = {
+      sks-db = {
         description = "SKS database server";
         after = [ "network.target" ];
         wantedBy = [ "multi-user.target" ];