### Summary

The documentation on https://docs.ansible.com/ansible/latest/collections/ansible/builtin/unarchive_module.html states that the module fully supports check-mode.
But the fact is that check-mode is not supported when it concerns a gzipped tar file cfr. https://github.com/ansible/ansible-modules-core/blob/00911a75ad6635834b6d28eef41f197b2f73c381/files/unarchive.py#L591
I was mislead by the '_fully_ supported' and noticed that the step was skipped in check-mode.
Wouldn't it make sense to adapt the documentation accordingly ?


### Issue Type

Documentation Report

### Component Name

https://github.com/ansible/ansible-modules-core/blob/00911a75ad6635834b6d28eef41f197b2f73c381/files/unarchive.py

### Ansible Version

```console
$ ansible --version
ansible [core 2.12.6]
  config file = ansible.cfg
  configured module search path = ['/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/local/lib/python3.9/dist-packages/ansible
  ansible collection location = /home/<user>/.ansible
  executable location = /usr/local/bin/ansible
  python version = 3.9.2 (default, Feb 28 2021, 17:03:44) [GCC 10.2.1 20210110]
  jinja version = 2.11.3
  libyaml = True
```


### Configuration

```console
# if using a version older than ansible-core 2.12 you should omit the '-t all'
$ ansible-config dump --only-changed -t all
```


### OS / Environment

Debian 11

### Additional Information

When the documentation is adapted, it is clear for everyone that unarchiving gzipped tar files is not check_mode compatible.

### Code of Conduct

- [X] I agree to follow the Ansible Code of Conduct
res_args['diff'] = {'prepared': check_results['diff']}
    
    if res_args.get('diff', True) and not module.check_mode:
        
        top_folders = []
        for filename in handler.files_in_archive:
            file_args['path'] = os.path.join(b_dest, to_bytes(filename, errors='surrogate_or_strict'))
            try:
                res_args['changed'] = module.set_fs_attributes_if_different(file_args, res_args['changed'], expand=False)
            except (IOError, OSError) as e:
                module.fail_json(msg="Unexpected error when accessing exploded file: %s" % to_native(e), **res_args)
            if '/' in filename:
                top_folder_path = filename.split('/')[0]
                if top_folder_path not in top_folders:
                    top_folders.append(top_folder_path)
        
        
        if top_folders:
            for f in top_folders:
                file_args['path'] = "%s/%s" % (dest, f)
                try:
                    res_args['changed'] = module.set_fs_attributes_if_different(file_args, res_args['changed'], expand=False)
                except (IOError, OSError) as e:
                    module.fail_json(msg="Unexpected error when accessing exploded file: %s" % to_native(e), **res_args)
    if module.params['list_files']:
        res_args['files'] = handler.files_in_archive
    module.exit_json(**res_args)
if __name__ == '__main__':
    main()