Proper branch name for mvfst
Proper branch name for mvfst

Summary:
Need to fix branch name for OSS mvfst so CI continues on.

Ran opensource/fbcode_builder/getdeps/facebook/update-all-github-actions.sh

Reviewed By: lnicco

Differential Revision: D32041656

fbshipit-source-id: f72aab91a3084814a5d3fa8643ae5f405908c313

facebook/wangle,facebook/wangle,facebook/wangle