nixos/dokuwiki: Don't force http with Caddy

Caddy usually expects just a hostname without scheme to do its automatic
HTTPS.  It is possible to get the old behavior (only HTTP) by setting
`services.caddy.virtualHosts.<host>.hostName`.

nixos/modules/services/web-apps/dokuwiki.nix

@@ -471,7 +471,7 @@ in
     services.caddy = {
       enable = true;
       virtualHosts = mapAttrs' (hostName: cfg: (
-        nameValuePair "http://${hostName}" {
+        nameValuePair hostName {
           extraConfig = ''
             root * ${pkg hostName cfg}/share/dokuwiki
             file_server

nixos/tests/dokuwiki.nix

@@ -78,6 +78,11 @@ let
       };
     };
 
+    services.caddy.virtualHosts = {
+      "site1.local".hostName = "http://site1.local";
+      "site2.local".hostName = "http://site2.local";
+    };
+
     networking.firewall.allowedTCPPorts = [ 80 ];
     networking.hosts."127.0.0.1" = [ "site1.local" "site2.local" ];
   };