Increase default timeout

I need to investigate why these calls take so long:

1. Deno Deploy cold starts?
2. Netlify rate limits or slowness? Can I make some use of caching?

modules/nixos/deno-netlify-ddns-client.nix

@@ -31,7 +31,7 @@ in {
     requestTimeout = mkOption {
       type = types.int;
       description = "The maximum number of seconds before the HTTP request times out.";
-      default = 30;
+      default = 180;
     };
     afterBootTime = mkOption {
       type = types.str;