Fix broken formatting in rest-api-config documentation

Change-Id: Ida22ab6b3aaa03148baab7873023e269c30f9f68

Documentation/rest-api-config.txt

diff --git a/Documentation/rest-api-config.txt b/Documentation/rest-api-config.txt
index 17e34f9..9ec21ec 100644
--- a/Documentation/rest-api-config.txt
+++ b/Documentation/rest-api-config.txt
@@ -339,7 +339,7 @@
   done
 ----
 
-[cache-operations]]
+[[cache-operations]]
 === Cache Operations
 --
 'POST /config/server/caches/'