Fix changelog from master merge

Author: kotfu

CHANGELOG.md

@@ -3,8 +3,10 @@
   * `cmd2` 2.5 supports Python 3.7+ (removed support for Python 3.6)
 * Enhancements
   * Removed dependency on `attrs` and replaced with [dataclasses](https://docs.python.org/3/library/dataclasses.html)
+  * add `allow_clipboard` initialization parameter and attribute to disable ability to
     add output to the operating system clipboard
 
+
 ## 2.4.3 (January 27, 2023)
 * Bug Fixes
   * Fixed ValueError caused when passing `Cmd.columnize()` strings wider than `display_width`.