add missing extras to docs

Author: kevinjqliu

mkdocs/docs/index.md

@@ -63,6 +63,9 @@ You can mix and match optional dependencies depending on your needs:
 | rest-sigv4    | Support for generating AWS SIGv4 authentication headers for REST Catalogs |
 | pyiceberg-core | Installs iceberg-rust powered core                                       |
 | datafusion    | Installs both PyArrow and Apache DataFusion                               |
+| hf            | Support for Hugging Face Hub                                              |
+| gcp-auth      | Support for Google Cloud authentication                                   |
+| entra-auth    | Support for Azure Entra authentication                                    |
 
 You either need to install `s3fs`, `adlfs`, `gcsfs`, or `pyarrow` to be able to fetch files from an object store.