Correct the link of 'OpenStack Documentation Contributor Guide'
Since Queens renamed from Contributor Guide to Documentation
Contributor Guide to distinguish this document from the new
document aimed at all new OpenStack contributors. So this
patch correct the link. Refer to
@@ -50,7 +50,7 @@ reStructuredText is a powerful language for generating web pages. The
documentation team has put together an `RST conventions`_ page with information
and links related to RST.
-.. _RST conventions: https://docs.openstack.org/contributor-guide/rst-conv.html
+.. _RST conventions: https://docs.openstack.org/doc-contrib-guide/rst-conv.html
Building Cinder's Documentation
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