### Summary

The [`validate_argument_spec` module](https://docs.ansible.com/ansible/latest/collections/ansible/builtin/validate_argument_spec_module.html) accepts the `argument_spec` argument.

This is all the page states:
> argument_spec : A dictionary like AnsibleModule argument_spec

But I can't find the definition of `argument_spec` anywhere.

It would be appreciated if it were documented. Thank you.

### Issue Type

Documentation Report

### Component Name

validate_argument_spec

### Ansible Version

```console
2.14.5
```


### Configuration

```console
n/a
```


### OS / Environment

n/a

### Additional Information

It is not clear what goes into that argument. There are two examples, but presumable they are not comprehensive.

### Code of Conduct

- [X] I agree to follow the Ansible Code of Conduct
EXAMPLES = r'''
- name: verify vars needed for this task file are present when included
  ansible.builtin.validate_argument_spec:
        argument_spec: '{{required_data}}'
  vars:
    required_data:
        # unlike spec file, just put the options in directly
        stuff:
            description: stuff
            type: str
            choices: ['who', 'knows', 'what']
            default: what
        but:
            description: i guess we need one
            type: str
            required: true
- name: verify vars needed for this task file are present when included, with spec from a spec file
  ansible.builtin.validate_argument_spec:
        argument_spec: "{{(lookup('ansible.builtin.file', 'myargspec.yml') | from_yaml )['specname']['options']}}"
- name: verify vars needed for next include and not from inside it, also with params i'll only define there
  block:
    - ansible.builtin.validate_argument_spec:
        argument_spec: "{{lookup('ansible.builtin.file', 'nakedoptions.yml'}}"
        provided_arguments:
            but: "that i can define on the include itself, like in it's C(vars:) keyword"
    - name: the include itself
      vars:
        stuff: knows
        but: nobuts!
'''