DOCS-12109: compound index field limit

Author: kay-kim

source/core/index-compound.txt

@@ -22,7 +22,7 @@ example of a compound index on two fields:
 .. include:: /images/index-compound-key.rst
 
 .. [#compound-index-field-limit]
-   MongoDB imposes a :limit:`limit of 31 fields for any compound index
+   MongoDB imposes a :limit:`limit of 32 fields for any compound index
    <Number of Indexed Fields in a Compound Index>`.
 
 Compound indexes can support queries that match on multiple fields.

source/reference/limits.txt

@@ -169,7 +169,7 @@ Indexes
 
 .. limit:: Number of Indexed Fields in a Compound Index
 
-   There can be no more than 31 fields in a compound index.
+   There can be no more than 32 fields in a compound index.
 
 .. limit:: Queries cannot use both text and Geospatial Indexes