Update fbsync (#425)

Summary:
Mainly to update GH workflow, since CI is not triggered on fbsync branch somehow.

Generated via
```
git cherry-pick 4d9e90a^..5732d84
```

on a fork of `fbsync` branch

Pull Request resolved: #425

Reviewed By: bearzx

Differential Revision: D37676633

Pulled By: wenleix

fbshipit-source-id: fdce7d4e058a47f8516d9fb6e084a726e1ffe68f

Author: wenleix

.github/workflows/macos.yml

@@ -1,10 +1,11 @@
 name: MacOS Build and Test
 on:
   push:
-    branches: [ main ]
+    branches: [ main, fbsync ]
   pull_request:
     branches:
       - main
+      - fbsync
       # For PR created by ghstack
       - gh/*/*/base
 

.github/workflows/ubuntu.yml

@@ -1,10 +1,11 @@
 name: Ubuntu Build and Test
 on:
   push:
-    branches: [ main ]
+    branches: [ main, fbsync ]
   pull_request:
     branches:
       - main
+      - fbsync
       # For PR created by ghstack
       - gh/*/*/base