### Summary

Based on feedback from a mastodon ansible user:

The first example of https://docs.ansible.com/ansible/latest/collections/ansible/builtin/apt_key_module.html#examples (the apt_key replacement) shows how a pgp key is downloaded and declared as trusted for a repository, but there is no validation of the key going on. Maybe the get_url task could include the checksum argument, to show that (and how) the key should be validated against a known good. Further down there is also an example of apt_key downloading a key without the id argument specified.

### Issue Type

Documentation Report

### Component Name

apt_key

### Ansible Version

```console
$ ansible --version
2.15
```


### 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
none
```


### OS / Environment

none

### Additional Information

The examples all use https URLs, so they do not expose you to just arbitrary MITM; but many projects use untrusted public mirrors to distribute packages and public keys, and instead post the fingerprint of the public key on the non-mirrored first-party website. You are then supposed to verify the downloaded key against that fingerprint (unfortunately a manual action since they post a PGP fingerprint and not a checksum), in order to protect against rogue mirror operators (AFAIK).

### Code of Conduct

- [X] I agree to follow the Ansible Code of Conduct
msg="Unable to add a key from file %s" % (keyfile),
                cmd=cmd,
                rc=rc,
                keyfile=keyfile,
                stdout=out,
                stderr=err,
            )
    return True
def remove_key(module, key_id, keyring):
    if keyring:
        cmd = '%s --keyring %s del %s' % (apt_key_bin, keyring, key_id)
    else:
        cmd = '%s del %s' % (apt_key_bin, key_id)
    (rc, out, err) = module.run_command(cmd)
    if rc != 0:
        module.fail_json(
            msg="Unable to remove a key with id %s" % (key_id),
            cmd=cmd,
            rc=rc,
            key_id=key_id,
            stdout=out,
            stderr=err,
        )
    return True
def main():
    module = AnsibleModule(
        argument_spec=dict(
            id=dict(type='str'),
            url=dict(type='str'),
            data=dict(type='str'),