DOCSP-21435: Apply what's new for 3.7 (#308)

Author: Chris Cho

source/whats-new.txt

@@ -7,7 +7,7 @@ What's New
 .. contents:: On this page
    :local:
    :backlinks: none
-   :depth: 3
+   :depth: 1
    :class: singlecol
 
 Learn what's new in:
@@ -17,6 +17,7 @@ Learn what's new in:
 * :ref:`Version 4.2 <version-4.2>`
 * :ref:`Version 4.1 <version-4.1>`
 * :ref:`Version 4.0 <version-4.0>`
+* :ref:`Version 3.7 <version-3.7>`
 * :ref:`Version 3.6 <version-3.6>`
 
 .. _version-4.4:
@@ -384,6 +385,16 @@ For a detailed list of breaking changes, removals, and associated JIRA tickets,
 see the detailed `list here <https://github.com/mongodb/node-mongodb-native/blob/4.0/docs/CHANGES_4.0.0.md>`__.
 
 
+.. _version-3.7:
+
+What's New in 3.7
+-----------------
+
+New features of the 3.7 Node.js driver release include:
+
+- Added support for load balancer mode while enabling the ``useUnifiedTopology`` option
+- Added support for :ref:`{+stable-api+} <nodejs-stable-api>` while enabling the ``useUnifiedTopology`` option
+
 .. _version-3.6:
 
 What's New in 3.6