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##### SUMMARY

The Git module encourages use of `StrictHostKeyChecking=no` with SSH, which makes the connection vulnerable to a MITM attack.

##### ISSUE TYPE

OpenSSH 7.5+ (2017-03-20) added a safer option which automatically accepts the key on first use but will not allow a MITM on subsequent connections: `StrictHostKeyChecking=accept-new` 

https://man.openbsd.org/ssh_config#StrictHostKeyChecking

It would be great if Ansible encouraged use of that mode by default in the documentation and to implement features such as the Git module's [`accept_hostkey`](https://github.com/ansible/ansible/blob/323d2adfcce9a53e906c2c4a40f6ac5fb32a0e68/lib/ansible/modules/git.py#L1103-L1108) feature.

##### ANSIBLE VERSION

```paste below
N/A
```

##### COMPONENT NAME
* `/modules/source_control/git.py`


result.update(changed=False)
            
            try:
                shutil.rmtree(tempdir)
            except OSError:
                pass
        else:
            try:
                shutil.move(new_archive, archive)
                shutil.rmtree(tempdir)
                result.update(changed=True)
            except OSError as e:
                module.fail_json(msg="Failed to move %s to %s" %
                                     (new_archive, archive),
                                 details=u"Error occurred while moving : %s"
                                         % to_text(e))
    else:
        
        git_archive(git_path, module, dest, archive, archive_fmt, archive_prefix, version)
        result.update(changed=True)
def main():
    module = AnsibleModule(
        argument_spec=dict(
            dest=dict(type='path'),
            repo=dict(required=True, aliases=['name']),
            version=dict(default='HEAD'),
            remote=dict(default='origin'),
            refspec=dict(default=None),
            reference=dict(default=None),
            force=dict(default='no', type='bool'),