Fix authentication issues
This PR fixes 3 authentication issues:
- Fix authentication when passing `token`.
- Fix authentication in `Audio.decode_example` and `Image.decode_example`.
- Fix authentication to resolve `data_files` in repositories without script.

This PR also fixes our CI so that we properly test when passing `token` and we do not use the token stored in `HfFolder`.

Fix #6126.

## Details


### Fix authentication when passing `token`

See c0a77dc943de68a17f23f141517028c734c78623

The root issue was caused when the `token` was set in an already instantiated `DownloadConfig` and thus not propagated to `self._storage_options`:

  ```python
  download_config.token = token
  ```

As this usage pattern is very common, the fix consists in overriding `DownloadConfig.__setattr__`.

This fixes authentication issues in the following functions:
- `load_dataset` and `load_dataset_builder`
- `Dataset.push_to_hub` and `Dataset.push_to_hub`
- `inspect.get_dataset_config_info`, `inspect.get_dataset_infos` and `inspect.get_dataset_split_names`

### Fix authentication in `Audio.decode_example` and `Image.decode_example`. 

See: 58e62af004b6b8b84dcfd897a4bc71637cfa6c3f

The `token` was not set because the `repo_id` was wrongly tried to be parsed from an HTTP URL (`"http://..."`), instead of an HFFileSystem URL (`"hf://"`)

### Fix authentication to resolve `data_files` in repositories without script

See: e4684fc1032321abf0d494b0c130ea7c82ebda80

This is fixed by passing `download_config` to the function `create_builder_configs_from_metadata_configs`