DOCSP-41551: dropone() return type (#370)

* DOCSP-41551: dropone return type

* add whats new item

* tense

* PV tech review comment

source/fundamentals/indexes.txt

@@ -440,31 +440,20 @@ The following example creates a unique, descending index on the ``theaterId`` fi
 Remove an Index
 ---------------
 
-You can remove any unused index except the default unique index on the
+You can delete any index from a collection except the default unique index on the
 ``_id`` field. To remove an index, pass the name of your index to the
 ``DropOne()`` method.
 
-The following example removes an ascending index on the ``title`` field
-in the ``sample_mflix.movies`` collection:
+The following example removes an index called ``title_1``
+from the ``sample_mflix.movies`` collection:
 
-.. io-code-block::
-   :copyable: true
-
-   .. input::
-      :language: go
-
-      coll := client.Database("sample_mflix").Collection("movies")
-      res, err := coll.Indexes().DropOne(context.TODO(), "title_1")
-      if err != nil {
-          panic(err)
-      }
-      fmt.Println(res)
-
-   .. output::
-      :language: none
-      :visible: false
+.. code-block:: go
 
-      {"nIndexesWas": {"$numberInt":"2"}}
+   coll := client.Database("sample_mflix").Collection("movies")
+   err := coll.Indexes().DropOne(context.TODO(), "title_1")
+   if err != nil {
+       panic(err)
+   }
 
 Additional Information
 ----------------------

source/whats-new.txt

@@ -87,6 +87,11 @@ The 2.0 {+driver-short+} release includes the following improvements and fixes:
 - The ``Distinct()`` method returns a struct that can be decoded into a
   specified type. See the :ref:`golang-retrieve-distinct` guide to learn more.
 
+- The ``IndexView.DropOne()`` method returns only an error, if present. In
+  previous versions, this method also returned the server response, which
+  contained the number of dropped indexes. See the
+  :ref:`golang-remove-index` section of the Indexes guide to learn more.
+
 .. _version-1.16:
 
 What's New in 1.16