PYTHON-4870 - Update changelog for MongoClient.address fix (mongodb#1931)

Author: NoahStapp

doc/changelog.rst

@@ -14,6 +14,9 @@ PyMongo 4.11 brings a number of changes including:
 - Dropped support for MongoDB 3.6.
 - Added support for free-threaded Python with the GIL disabled. For more information see:
   `Free-threaded CPython <https://docs.python.org/3.13/whatsnew/3.13.html#whatsnew313-free-threaded-cpython>`_.
+- :attr:`~pymongo.asynchronous.mongo_client.AsyncMongoClient.address` and
+  :attr:`~pymongo.mongo_client.MongoClient.address` now correctly block when called on unconnected clients
+  until either connection succeeds or a server selection timeout error is raised.
 
 Issues Resolved
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