docs: simplify conf.py and fix compatibility with upcoming Sphinx 6.0
Change-Id: Iad9546136d4ee7a3e94dc537701b592a988624af
diff --git a/docs/index.rst b/docs/index.rst
index 0cd704e..3a40dfc 100644
--- a/docs/index.rst
+++ b/docs/index.rst
@@ -23,4 +23,4 @@
-------
NAC is an open source project licensed under the LGPL version 3. For more information about
-the license, refer to `COPYING.md <https://github.com/named-data/name-based-access-control/blob/master/COPYING.md>`_.
+the license, refer to `COPYING.md <https://github.com/named-data/name-based-access-control/blob/new/COPYING.md>`_.