docs: fix links to source tarballs

Change-Id: Id04ca492c2c91f3c27f5de28c616171f8b0585aa
diff --git a/docs/RELEASE_NOTES.rst b/docs/RELEASE_NOTES.rst
index 72da691..04e2f84 100644
--- a/docs/RELEASE_NOTES.rst
+++ b/docs/RELEASE_NOTES.rst
@@ -1,4 +1,4 @@
 Release Notes
-+++++++++++++
+=============
 
 .. include:: release-notes-latest.rst