Adding the correct task tag (#3)

- Adding the correct task tag (7a0d68a7199764465fe34ea06c506797b78cd53e)


Co-authored-by: Vaibhav Srivastav <reach-vb@users.noreply.huggingface.co>

README.md

@@ -1,5 +1,6 @@
 ---
 license: apache-2.0
+pipeline_tag: text-to-speech
 ---
 # Step-Audio-TTS-3B