Address review feedback

Author: aclark4life

doc/changelog.rst

@@ -6,13 +6,6 @@ Changes in Version 4.17.0 (2026/XX/XX)
 
 PyMongo 4.17 brings a number of changes including:
 
-- Remove unused validation functions from pymongo/common.py
-
-  - ``validate_positive_integer_or_none`` (internal helper, no longer used)
-  - ``validate_int_or_basestring`` (internal helper, no longer used)
-  - ``validate_auth_option`` (validated auth mechanism properties but was never
-    used)
-
 - Added the :meth:`~pymongo.asynchronous.client_session.AsyncClientSession.bind` and :meth:`~pymongo.client_session.ClientSession.bind` methods
   that allow users to bind a session to all database operations within the scope of a context manager instead of having to explicitly pass the session to each individual operation.
   See <PLACEHOLDER> for examples and more information.