Add v2.0.12 release notes to index

Signed-off-by: Stewart Smith <stewart@linux.ibm.com>
diff --git a/doc/release-notes/index.rst b/doc/release-notes/index.rst
index dd4bfb9..d3ebb68 100644
--- a/doc/release-notes/index.rst
+++ b/doc/release-notes/index.rst
@@ -43,6 +43,7 @@
    v2.0.9
    v2.0.10
    v2.0.11
+   v2.0.12
 
 v2.1
 ----