### Summary

https://docs.ansible.com/ansible/latest/collections/ansible/builtin/mandatory_filter.html makes no mention of the `msg` argument that was introduced in 0e7e3c0ae89a70c386168827b0c9defb956bee7e

### Issue Type

Documentation Report

### Component Name

lib/ansible/plugins/filter/mandatory.yml

### Ansible Version

```console
n/a
```


### Configuration

```console
n/a
```


### OS / Environment

n/a

### Additional Information

n/a

### Code of Conduct

- [X] I agree to follow the Ansible Code of Conduct
comment_styles = {
        'plain': {
            'decoration': '# '
        },
        'erlang': {
            'decoration': '% '
        },
        'c': {
            'decoration': '// '
        },
        'cblock': {
            'beginning': '/*',
            'decoration': ' * ',
            'end': ' */'
        },
        'xml': {
            'beginning': '<!--',
            'decoration': ' - ',
            'end': '-->'
        }
    }
    
    style_params = comment_styles[style]
    if 'decoration' in kw:
        prepostfix = kw['decoration']
    else: