[master] 746f83945 fix typo

[hermunn]

commit 746f839454cac878aae0803b5d33a48b7f0ef7f1
Author: Valentin Matei <matheuzzy at gmail.com>
Date:   Wed Nov 7 13:19:20 2018 +0200

    fix typo

diff --git a/doc/sphinx/whats-new/changes-6.1.rst b/doc/sphinx/whats-new/changes-6.1.rst
index 3ceffc093..f9579b76c 100644
--- a/doc/sphinx/whats-new/changes-6.1.rst
+++ b/doc/sphinx/whats-new/changes-6.1.rst
@@ -3,7 +3,7 @@
 Changes in Varnish 6.1
 ======================
 
-This is release is a maintenance release, so while there are many actual
+This release is a maintenance release, so while there are many actual
 changes, and of course many bugfixes, they should not have little to no
 impact on running Varnish installations.