docs: add build badge

README.md

@@ -6,12 +6,12 @@
 # Serverless ChatGPT with RAG using LangChain.js
 
 [![Open project in GitHub Codespaces](https://img.shields.io/badge/Codespaces-Open-blue?style=flat-square&logo=github)](https://codespaces.new/Azure-Samples/serverless-chat-langchainjs?hide_repo_select=true&ref=main)
-![Node version](https://img.shields.io/badge/Node.js->=20-grass?style=flat-square)
+[![Build Status](https://img.shields.io/github/actions/workflow/status/Azure-Samples/serverless-chat-langchainjs/build-test.yaml?style=flat-square&label=Build)](https://github.com/Azure-Samples/serverless-chat-langchainjs/actions)
+![Node version](https://img.shields.io/badge/Node.js->=20-3c873a?style=flat-square)
 [![Ollama + Mistral](https://img.shields.io/badge/Ollama-Mistral-ff7000?style=flat-square)](https://ollama.com/library/mistral)
 [![TypeScript](https://img.shields.io/badge/TypeScript-blue?style=flat-square&logo=typescript&logoColor=white)](https://www.typescriptlang.org)
 [![License](https://img.shields.io/badge/License-MIT-yellow?style=flat-square)](LICENSE)
 
-<!-- [![Build Status](https://img.shields.io/github/actions/workflow/status/Azure-Samples/serverless-chat-langchainjs/build?style=flat-square)](https://github.com/Azure-Samples/serverless-chat-langchainjs/actions) -->
 <!-- [![Watch how to use this sample on YouTube](https://img.shields.io/badge/YouTube-Watch-d95652.svg?style=flat-square&logo=youtube)]() -->
 
 :star: If you like this sample, star it on GitHub — it helps a lot!