Datasets.datafiles resolve_pattern `TypeError: can only concatenate tuple (not "str") to tuple`
### Describe the bug

in data_files.py, line 332, 
`fs,  _, _ = get_fs_token_paths(pattern, storage_options=storage_options)`
If we run the code on AWS, as fs.protocol will be a tuple like: `('file', 'local')`
So,  `isinstance(fs.protocol, str) == False` and
`protocol_prefix = fs.protocol + "://" if fs.protocol != "file" else ""` will raise 
`TypeError: can only concatenate tuple (not "str") to tuple`.

### Steps to reproduce the bug

Steps to reproduce:
1. Run on a cloud server like AWS,
2. `import datasets.data_files as datafile`
3. datafile.resolve_pattern('path/to/dataset', '.')
4. `TypeError: can only concatenate tuple (not "str") to tuple`

### Expected behavior

Should return path of the dataset, with fs.protocol at the beginning

### Environment info

- `datasets` version: 2.14.0
- Platform: Linux-3.10.0-1160.119.1.el7.x86_64-x86_64-with-glibc2.17
- Python version: 3.8.19
- Huggingface_hub version: 0.23.5
- PyArrow version: 16.1.0
- Pandas version: 1.1.5