fix(docs): clarify lazy.nvim loading and add correct setup example

Author: attilarepka

README.md

@@ -28,7 +28,12 @@ use({ "attilarepka/header.nvim", config = function() require("header").setup() e
 with [lazy.nvim](https://github.com/folke/lazy.nvim)
 
 ```lua
-{"attilarepka/header.nvim", config = true}
+{
+    "attilarepka/header.nvim",
+    config = function()
+        require("header").setup()
+    end,
+},
 ```
 
 ## Setup

lua/header/license.lua

@@ -1,4 +1,3 @@
-local util = require("header.util")
 local M = {}
 
 function M.scan_license_files()