docs: Fix on_colors example (#197)

README.md

@@ -166,10 +166,10 @@ require("tokyonight").setup({
   },
   sidebars = { "qf", "vista_kind", "terminal", "packer" },
   -- Change the "hint" color to the "orange" color, and make the "error" color bright red
-  on_colors = function(colors) {
+  on_colors = function(colors)
     colors.hint = colors.orange
     colors.error = "#ff0000"
-  }
+  end
 })
 ```