bpo-43391: Remove the broken Python 2.4 link from the comment (GH-24736)

diff --git a/Lib/subprocess.py b/Lib/subprocess.py
index aa107cb..e4ca5f5 100644
--- a/Lib/subprocess.py
+++ b/Lib/subprocess.py
@@ -5,7 +5,6 @@
 # Copyright (c) 2003-2005 by Peter Astrand <astrand@lysator.liu.se>
 #
 # Licensed to PSF under a Contributor Agreement.
-# See http://www.python.org/2.4/license for licensing details.
 
 r"""Subprocesses with accessible I/O streams