DOCS-16339 Removes note from config.system.sessions (#4670)

Co-authored-by: Kenneth P. J. Dyer <kenneth.dyer@monodb.com>

Author: kennethdyer

source/reference/config-database.txt

@@ -465,14 +465,10 @@ instance.
 
    In a sharded cluster, the ``system.sessions`` collection is sharded.
 
-   - When adding a shard to the sharded cluster, if the shard to add
-     already contains its own ``system.sessions`` collection, MongoDB
-     drops the new shard's ``system.sessions`` collection during the
-     add process.
-
-   - Starting in version 4.4 (and 4.2.7), MongoDB automatically splits
-     the ``system.sessions`` collection into at least 1024 chunks and
-     distributes the chunks uniformly across shards in the cluster.
+   When adding a shard to the sharded cluster, if the shard to add
+   already contains its own ``system.sessions`` collection, MongoDB
+   drops the new shard's ``system.sessions`` collection during the
+   add process.
 
 .. data:: config.transactions