Fix bug when server not explicitely defined in configuration but installed

init.lua

@@ -463,7 +463,7 @@ mason_lspconfig.setup_handlers {
       capabilities = capabilities,
       on_attach = on_attach,
       settings = servers[server_name],
-      filetypes = servers[server_name].filetypes,
+      filetypes = (servers[server_name] or {}).filetypes,
     }
   end
 }