Fix the spec for OptionParser.parse_head!/2

Signed-off-by: Andrea Leopardi <[email protected]>

Author: whatyouhide

lib/elixir/lib/option_parser.ex

@@ -239,7 +239,7 @@ defmodule OptionParser do
       --verbose : Missing argument of type integer
       --source : Expected type integer, got "lib"
   """
-  @spec parse_head!(argv, options) :: {parsed, argv, errors} | no_return
+  @spec parse_head!(argv, options) :: {parsed, argv} | no_return
   def parse_head!(argv, opts \\ []) when is_list(argv) and is_list(opts) do
     case parse_head(argv, opts) do
       {parsed, args, []} -> {parsed, args}