Update correct download command

Remove --repo_id to solve the error of unrecognized arguments for download.

README.md

@@ -38,7 +38,7 @@ To download one of the `.mlpackage` folders to the `models` directory:
 huggingface-cli download \
   --local-dir models \
   --local-dir-use-symlinks False \
-  --repo_id apple/coreml-mistral-7b-instruct-v0.3 \
+  apple/coreml-mistral-7b-instruct-v0.3 \
   --include "StatefulMistral7BInstructInt4.mlpackage/*"
 ```