Update changelog about jupyterhub 4

Author: consideRatio

docs/source/changelog.md

@@ -14,14 +14,11 @@ this list should be updated.
 
 - K8s 1.23 is now required.
 - The Helm chart's provided images now use Python 3.11 instead of Python 3.9.
-- JupyterHub 3.0.0 is upgraded to 4.0.0b2.
-  - Although it is not officially supported to run a JupyterHub server with a
-    major version different from the singleuser servers' `jupyterhub-singleuser`
-    version, it seems possible during this upgrade. We recommend your singleuser
-    images are upgraded as soon as practical, before or after the JupyterHub
-    chart is upgraded. We expect running user servers to be able to keep running
-    during the upgrade.
-  - Please refer to the [JupyterHub changelog] for details
+- JupyterHub 3.0.0 is upgraded to 4.0.0.
+  - Please refer to the [JupyterHub changelog] for details, but note that this
+    upgrade won't require user servers to be restarted or first install version
+    4 of `jupyterhub` (PyPI) or `jupyterhub-base` (conda-forge) in their user
+    environments.
 - KubeSpawner 4.2.0 is upgraded to 5.0.0
   - Please read to the [KubeSpawner changelog]'s breaking changes and be aware
     that configuring [`singleuser.extraEnv`](schema_singleuser.extraEnv) is to