Add SSF Best practices badge (#6604)

Work in progress to ensure we meet SSF best practices:
https://www.bestpractices.dev/en/projects/9530

README.md

@@ -2,6 +2,7 @@
 [![PyPI version](https://badge.fury.io/py/deepspeed.svg)](https://pypi.org/project/deepspeed/)
 [![Downloads](https://static.pepy.tech/badge/deepspeed)](https://pepy.tech/project/deepspeed)
 [![Build](https://badgen.net/badge/build/check-status/blue)](#build-pipeline-status)
+[![OpenSSF Best Practices](https://www.bestpractices.dev/projects/9530/badge)](https://www.bestpractices.dev/projects/9530)
 [![Twitter](https://img.shields.io/twitter/follow/MSFTDeepSpeed)](https://twitter.com/intent/follow?screen_name=MSFTDeepSpeed)
 [![Japanese Twitter](https://img.shields.io/badge/%E6%97%A5%E6%9C%AC%E8%AA%9ETwitter-%40MSFTDeepSpeedJP-blue)](https://twitter.com/MSFTDeepSpeedJP)
 [![Chinese Zhihu](https://img.shields.io/badge/%E7%9F%A5%E4%B9%8E-%E5%BE%AE%E8%BD%AFDeepSpeed-blue)](https://www.zhihu.com/people/deepspeed)