docs(CHANGES): Update for python 3 changes

Author: tony

CHANGES

@@ -8,11 +8,15 @@ Generally speaking, refactor / magic is in the process of being stripped
 out in the next few releases. The API is subject to change significantly
 in pre-1.0 builds.
 
+[#271]:
 - Big version bump (0.5 -> 0.9)
 - Remove Python 2.7 support
 - Add annotations
 - Change `libvcs.git.GitRepo.status()` to return `GitStatus` named tuple
 - Breaking change: Repo objects now require `repo_dir` to be passed
+- Update black to 21.6b0
+
+[#271]: https://github.com/vcs-python/libvcs/pull/271
 
 ## libvcs 0.5 (2020-08-11)