Allow disabling remote signing in REST Catalog #3888

Feature Request / Improvement

When using a REST Catalog (e.g. Lakekeeper), pyiceberg gets remote signing details from the catalog.

However, sometimes it would be useful to not use remote signing, in the case where the process performing the operations has access to the S3 endpoint through secret access keys. This is because remote signing requires a network round trip (plus any authorisation on server side).

It would be great if we could disable remote signing by respecting the s3.signer catalog property if it is empty.

The FileIO object gets created in pyiceberg/catalog/rest/__init__.py:

return Table(
    identifier=identifier_tuple,
    metadata_location=table_response.metadata_location,  # type: ignore
    metadata=table_response.metadata,
    io=self._load_file_io(
        {**table_response.metadata.properties, **table_response.config}, table_response.metadata_location
    ),
    catalog=self,
    config=table_response.config,
)

This doesn't use the catalog properties that have been passed to the REST catalog init as far as I can tell.

I might be wrong, but I don't think Support storage-credentials in REST catalog LoadTableResult- #3042
fixes this, because it still uses the response from the catalog.

Thanks!