DOCSP-13725 update returns section with array name

Author: andf-mongodb

source/reference/method/db.collection.insertMany.txt

@@ -77,10 +77,12 @@ Definition
 
       A document containing:
 
-      - A boolean ``acknowledged`` as ``true`` if the operation ran with
-        :term:`write concern` or ``false`` if write concern was disabled
+      - An ``acknowledged`` boolean, set to ``true`` if the operation
+        ran with :term:`write concern` or ``false`` if write concern
+        was disabled
 
-      - An array of ``_id`` for each successfully inserted documents
+      - An ``insertedIds`` array, containing ``_id`` values for each
+        successfully inserted document
 
 Behaviors
 ---------