fix: deprecation warnings

Signed-off-by: Lander Van den Bulcke <landervandenbulcke@gmail.com>

plugins/lang/ruby.nix

@@ -1,11 +1,16 @@
 { pkgs, ... }:
 {
+  withRuby = false;
+
   plugins.lsp.servers = {
     rubocop.enable = true;
     ruby_lsp.enable = true;
   };
 
   extraPackages = with pkgs; [
-    rubyPackages.rubocop-performance
+    gcc # needed for compiling native extensions
+    gnumake
+    libyaml
+    pkg-config
   ];
 }