update monotonic blurb

Author: kay-kim

source/includes/extracts-concurrency-consistency-recency.yaml

@@ -86,7 +86,7 @@ content: |
 ref: monotonic-writes
 content: |
    MongoDB provides  monotonic write guarantees for standalone
-   :program:`mongod` instances, replica sets, and sharded clusters.
+   :program:`mongod` instances and replica sets.
 
    Suppose an application performs a sequence of operations that
    consists of a write operation *W*\ :sub:`1` followed later in the