Update README.md (#998)

Signed-off-by: Brittany <[email protected]>

Author: bvrockwell

README.md

@@ -6,7 +6,7 @@
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-| <a href="https://docs.vllm.ai/projects/tpu/en/latest/"><b>Documentation</b></a> | <a href="https://blog.vllm.ai/"><b>Blog</b></a> | <a href="https://discuss.vllm.ai/c/hardware-support/google-tpu-support/27"><b>User Forum</b></a> | <a href="https://join.slack.com/share/enQtOTY2OTUxMDIyNjY1OS00M2MxYWQwZjAyMGZjM2MyZjRjNTA0ZjRkNjkzOTRhMzg0NDM2OTlkZDAxOTAzYmJmNzdkNDc4OGZjYTUwMmRh"><b>Developer Slack</b></a> |
+| <a href="https://docs.vllm.ai/projects/tpu/en/latest/"><b>Documentation</b></a> | <a href="https://blog.vllm.ai/"><b>Blog</b></a> | <a href="https://discuss.vllm.ai/c/hardware-support/google-tpu-support/27"><b>User Forum</b></a> | <a href="https://slack.vllm.ai"><b>Developer Slack</b></a>  (#sig-tpu) |
 </p>
 
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