nixos/networking: fix extraHosts generation

nixos/common.nix

@@ -99,22 +99,15 @@ in
 
     extraHosts =
       let
-        subdomains = [
+        subdomains = [ "git" ];
-          ""
+
-          ".git"
+        inherit (config.networking) fqdn;
-        ];
+        hosts = [ fqdn ] ++ map (sub: "${sub}.${fqdn}") subdomains;
       in
-      builtins.foldl' (
+      lib.concatMapStrings (host: ''
-        hosts-acc: domain-prefix:
-        let
-          host = "${domain-prefix}${config.networking.fqdn}";
-        in
-        hosts-acc
-        + ''
         127.0.0.1 ${host}
         ::1 ${host}
-        ''
+      '') hosts;
-      ) "" subdomains;
   };
 
   virtualisation.podman.enable = true;