docs: Update Slack group link README.md (TabbyML#653)

README.md

@@ -91,7 +91,7 @@ apt-get install protobuf-compiler libopenblas-dev
 ... and don't forget to submit a [Pull Request](https://github.com/TabbyML/tabby/compare)
 
 ## 🌍 Community
-- #️⃣ [Slack](https://join.slack.com/t/tabbyml/shared_invite/zt-22thejc0z-7ePKeWNCHPX31pEtnT4oYQ) - connect with the TabbyML community 
+- #️⃣ [Slack](https://join.slack.com/t/tabbycommunity/shared_invite/zt-1xeiddizp-bciR2RtFTaJ37RBxr8VxpA) - connect with the TabbyML community 
 - 🎤 [Twitter / X](https://twitter.com/Tabby_ML) - engage with TabbyML for all things possible 
 - 📚 [LinkedIn](https://www.linkedin.com/company/tabbyml/) - follow for the latest from the community 
 - 💌 [Newsletter](https://tinyletter.com/tabbyml/) - subscribe to unlock Tabby insights and secrets