Update model metadata to set pipeline tag to the new `text-ranking` (#1)

- Update model metadata to set pipeline tag to the new `text-ranking` (4ff465e7f32998da3c1037c75c417e73fe78d579)


Co-authored-by: Tom Aarsen <tomaarsen@users.noreply.huggingface.co>

README.md

@@ -9,6 +9,7 @@ tags:
 - tinyllama
 - rag
 - rerank
+pipeline_tag: text-ranking
 ---
 ```python
 template = """<s><|system|>