use on_init to check golangci_lint_ls version

also ensure language servers are compatible with navbuddy before
registering them

lua/plugins/lsp/on_attach.lua

@@ -1,5 +1,7 @@
 return function(client, bufnr)
-  require('nvim-navbuddy').attach(client, bufnr)
+  if client.server_capabilities.documentSymbolProvider then
+    require('nvim-navbuddy').attach(client, bufnr)
+  end
 
   local nmap = function(keys, func, desc)
     if desc then