nginx: drop recommendedZstdSettings

nixpkgs no longer recommends it.

clanModules/nginx/default.nix

@@ -38,7 +38,6 @@
       recommendedOptimisation = lib.mkDefault true;
       recommendedProxySettings = lib.mkDefault true;
       recommendedTlsSettings = lib.mkDefault true;
-      recommendedZstdSettings = lib.mkDefault true;
 
       # Nginx sends all the access logs to /var/log/nginx/access.log by default.
       # instead of going to the journal!