update playlist

Author: asottile

README.md

@@ -639,3 +639,4 @@ the full [playlist] is on youtube
 1. [why do .pth files run twice? (and fixing it!)](https://youtu.be/X9IYhsNUIe8)
 1. [annotated tags](https://youtu.be/GhWbJHdCkOA)
 1. [typing \*args and \*\*kwargs](https://youtu.be/2Uo3iD8lJh4)
+1. [does git 2.54 make pre-commit obsolete?](https://youtu.be/8Jwg_mM9WYc)