DOCSP-19860 add config.set info for VSCode (#171)

* DOCSP-19860 add config.set info for VSCode

* Add path note

* path to PATH

Author: Dave

source/reference/editor-mode.txt

@@ -246,10 +246,20 @@ Using Visual Studio as an External Editor
 Visual Studio requires a special parameter to work as an external
 editor. Use ``--wait`` with Visual Studio.
 
+Set an environment variable:
+
 .. code-block:: javascript
 
    export EDITOR="/usr/local/bin/code --wait"
 
+You can also set the editor with :ref:`config.set()
+<mongosh-shell-settings>`. If Visual Studio is in your ``PATH``, open
+:binary:`~bin.mongosh` and run:
+
+.. code-block:: javascript
+
+   config.set("editor", "code --wait")
+
 If you use Visual Studio, you can also use the `MongoDB VS Code
 Extension <https://www.mongodb.com/products/vs-code>`__.