mailserver: adapt to deprecated and new types of certificateScheme

sp-modules/simple-nixos-mailserver/config.nix

@@ -1,4 +1,4 @@
-{ config, lib, ... }:
+mailserverDate: { config, lib, ... }:
 let
   sp = config.selfprivacy;
 in
@@ -62,7 +62,11 @@ in
         "admin@${sp.domain}" = "${sp.username}@${sp.domain}";
       };
 
-      certificateScheme = "manual";
+      certificateScheme =
+        if builtins.compareVersions mailserverDate "20230525011002"
+          >= 0
+        then "manual"
+        else 1;
       certificateFile = "/var/lib/acme/${sp.domain}/fullchain.pem";
       keyFile = "/var/lib/acme/${sp.domain}/key.pem";
 

sp-modules/simple-nixos-mailserver/flake.nix

@@ -6,7 +6,6 @@
 
   outputs = { self, mailserver }: {
     nixosModules.default = args@{ config, ... }:
-      # tricks to rename (alias) the original module
       let
         module = mailserver.nixosModules.default args;
       in
@@ -14,12 +13,13 @@
         imports = [
           module
           {
+            # tricks to rename (alias) the original module
             config.mailserver =
               config.selfprivacy.modules.simple-nixos-mailserver;
             options.selfprivacy.modules.simple-nixos-mailserver =
               module.options.mailserver;
           }
-          ./config.nix
+          (import ./config.nix mailserver.lastModifiedDate)
         ];
       };
     configPathsNeeded =