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` (cdc1859b23d99bd1f24f699a15a4c9ebbe72684f)


Co-authored-by: Tom Aarsen <[email protected]>

README.md

@@ -11,7 +11,7 @@ tags:
 base_model: microsoft/MiniLM-L12-H384-uncased
 datasets:
 - microsoft/ms_marco
-pipeline_tag: text-classification
+pipeline_tag: text-ranking
 library_name: sentence-transformers
 metrics:
 - map