Add mvfst as the dependency for opensource fboss manifest

Summary: As D92344556, this diff makes sure we will have the synced meta dependency list for FBOSS OSS

Reviewed By: srikrishnagopu

Differential Revision: D92346848

fbshipit-source-id: 7ee54777614cba651b7a8fefb93ff47137abd304

Author: Joseph Wu

build/fbcode_builder/manifests/fboss

@@ -20,6 +20,7 @@ folly
 fb303
 wangle
 fizz
+mvfst
 fmt
 libsodium
 googletest