Allow override tsserver formatter args (#921)

lua/lsp/tsserver-ls.lua

@@ -11,8 +11,7 @@ O.formatters.filetype["javascriptreact"] = {
   function()
     return {
       exe = prettier_instance,
-      -- TODO: allow user to override this
-      args = { "--stdin-filepath", vim.api.nvim_buf_get_name(0), "--single-quote" },
+      args = O.lang.tsserver.formatter.args,
       stdin = true,
     }
   end,