Update the leak check script copyright headers as well.
diff --git a/leakcheck/context-verify-callback.py b/leakcheck/context-verify-callback.py
index 5e49d7a..0ae586b 100644
--- a/leakcheck/context-verify-callback.py
+++ b/leakcheck/context-verify-callback.py
@@ -1,4 +1,5 @@
-# Copyright (C) Jean-Paul Calderone 2008, All rights reserved
+# Copyright (C) Jean-Paul Calderone
+# See LICENSE for details.
 #
 # Stress tester for thread-related bugs in global_verify_callback in
 # src/ssl/context.c.  This will reliably segfault if context.c isn't a