remove unused function from lsp.lua and add more lsp plugins!

after/plugin/lsp.lua

@@ -35,13 +35,6 @@ set_lsp_sign("DiagnosticSignInfo" , "i")
 set_lsp_sign("DiagnosticSignHint" , "h")
 
 local function lsp_settings()
-  local sign = function(opts)
-    vim.fn.sign_define(opts.name, {
-      texthl = opts.name,
-      text = opts.text,
-      numhl = ''
-    })
-  end
 
   vim.diagnostic.config({
     virtual_text = false,