DOCSP-27869 non-genuine warning (#250)

* DOCSP-27869 non-genuine warning

* Review feedback

Author: Dave Cuthbert

source/connect.txt

@@ -266,6 +266,16 @@ following actions:
 
 - Press ``Ctrl`` + ``C`` twice.
 
+.. _mongosh-work-alike-deployments:
+
+Non-genuine Deployments
+-----------------------
+
+Starting in ``mongosh`` 1.7.0, the shell displays a warning message when
+connected to non-genuine MongoDB instances. Non-genuine instances may
+behave differently from the official MongoDB instances due to missing,
+inconsistent, or incomplete features.
+
 Limitations
 -----------