Add task to model card for discoverability (#6)

- Add task to model card for discoverability (8cdd79fa6820f522d9790ecf48267ebbf7093729)


Co-authored-by: Omar Sanseviero <osanseviero@users.noreply.huggingface.co>

README.md

@@ -6,6 +6,7 @@ tags:
 - glm
 - chatglm
 - thudm
+pipeline_tag: text2text-generation
 ---
 # ChatGLM2-6B
 <p align="center">