docs(CHANGES): Note update

Author: tony

CHANGES

@@ -14,6 +14,13 @@ $ pip install --user --upgrade --pre libtmux
 
 <!-- Maintainers and contributors: Insert change notes for the next release above -->
 
+### Breaking changes
+
+- Fix `distutils` warning, vendorize `LegacyVersion` (#351)
+
+  Removal of reliancy on `distutils.version.LooseVersion`, which does not
+  support `tmux(1)` versions like `3.1a`.
+
 ### Features
 
 - `Window.split_window()` and `Session.new_window()` now support an optional