update copyright in mktests.sh

[Paul Eggert]

I installed this obvious patch:

2004-01-26  Paul Eggert  <address@hidden>

        * tests/mktests.sh: Update copyright date to 2004, since some tests
        have changed in 2004.

--- mktests.sh.~1.37.~  Tue Nov  4 04:32:03 2003
+++ mktests.sh  Mon Jan 26 15:23:30 2004
@@ -1,7 +1,7 @@
 #! /bin/sh
 
 # Build some of the Autoconf test files.
-# Copyright (C) 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
+# Copyright (C) 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
 
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -227,7 +227,7 @@ do
     ## Do not edit by hand.  ##
     ## --------------------- ##
 
-    # Copyright (C) 2000, 2001, 2003 Free Software Foundation, Inc.
+    # Copyright (C) 2000, 2001, 2003, 2004 Free Software Foundation, Inc.
 
     AT_BANNER([Testing autoconf/$base macros.])