Fix formatting issue with Codecov badge

Author: brettcannon

.github/CONTRIBUTING.rst

@@ -8,8 +8,9 @@ Build Status
 
   + .. image:: https://travis-ci.org/python/cpython.svg?branch=master
        :target: https://travis-ci.org/python/cpython
+  
   + .. image:: https://codecov.io/gh/python/cpython/branch/master/graph/badge.svg
-       :target: https://codecov.io/gh/python/cpython
+       :target: https://codecov.io/gh/python/cpython
 
   + `Stable buildbots <http://buildbot.python.org/3.x.stable/>`_