message: Adding link to SST 1.0 Conf in README
diff: <a href="https://github.com/serverless-stack/serverless-stack/actions/workflows/ci.yml"><img alt="Build status" src="https://img.shields.io/github/workflow/status/serverless-stack/serverless-stack/CI?style=flat-square" /></a>
  </p>
  +<p align="center">
  + <a href="https://v1conf.sst.dev">
  + <img alt="SST 1.0 Conf" src="https://v1conf.sst.dev/assets/social-share-no-logo.png" width="600" />
  + </a>
  +</p>
  +
  ---
  Serverless Stack (SST) is a framework that makes it easy to build serverless apps. It's an extension of [AWS CDK](https://aws.amazon.com/cdk/) and it features:
  