Add appropriate tags

This PR ensures the "how to use" button appears on the top right (with a Transformers code snippet), along with the appropriate pipeline tag.

Would be great to update all models :)

README.md

@@ -1,6 +1,8 @@
 ---
 license: mit
 language: fr
+library_name: transformers
+pipeline_tag: feature-extraction
 datasets:
   - uonlp/CulturaX
   - oscar