cmd/docs: Add a versionchanged note

Constantin1489 · Constantin1489 · commit 2dff7ca1e34a · 2023-12-02T00:47:04.000+09:00
diff --git a/Doc/library/cmd.rst b/Doc/library/cmd.rst
@@ -42,6 +42,9 @@ interface.
    :attr:`use_rawinput` attribute to ``False``, otherwise *stdin* will be
    ignored.
 
+   .. versionchanged:: 3.11
+      ``completekey='tab'`` is replaced by ``'^I'`` for ``editline``.
+
 
 .. _cmd-objects:
 
