Update changelog

Author: WyattBlue

CHANGELOG.md

@@ -4,7 +4,7 @@
  - Deprecate `--keep-tracks-separate`, it's behavior is now the default. Use `--mix-audio-streams` for the old behavior.
  - Remove deprecated "copy" codec (auto-editor never does remuxing).
  - Require NumPy >= 2.
- - Use BasswoodAV (`basswood-av`) instead of PyAV (`pyav`).
+ - Switch from PyAV to [BasswoodAV](https://github.com/basswood-io/BasswoodAV)
 
 ## Features
  - Make video rendering 11% faster, rendering should be 19% faster overall.