Issue #27378: Remove an outdated reference from regex HOWTO

Patch by Matt Morrison.

Doc/howto/regex.rst

@@ -374,9 +374,7 @@ module.  If you have :mod:`tkinter` available, you may also want to look at
 :source:`Tools/demo/redemo.py`, a demonstration program included with the
 Python distribution.  It allows you to enter REs and strings, and displays
 whether the RE matches or fails. :file:`redemo.py` can be quite useful when
-trying to debug a complicated RE.  Phil Schwartz's `Kodos
-<http://kodos.sourceforge.net/>`_ is also an interactive tool for developing and
-testing RE patterns.
+trying to debug a complicated RE.
 
 This HOWTO uses the standard Python interpreter for its examples. First, run the
 Python interpreter, import the :mod:`re` module, and compile a RE::