Expose package version in GitPair.version fn

Co-authored-by: amadeu01 <amadeu01@users.noreply.github.com>

Author: wevtimoteo

lib/git_pair.ex

@@ -2,4 +2,8 @@ defmodule GitPair do
   @moduledoc """
   Documentation for `GitPair`.
   """
+
+  @version Mix.Project.config[:version]
+
+  def version(), do: @version
 end