Set the s3 socket connection timeout to be 0.5 secs.

Summary:
as the title.

Test Plan: manually test, it fails fast.

Reviewers: mgorven, lguo

CC:

Task ID: #5239513

Blame Rev:
Merge pull request #2 from DikangGu/v0.7.0insta2

Set the s3 socket connection timeout to be 0.5 secs.