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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`


submodules_updated = False
    if recursive and not bare:
        submodules_updated = submodules_fetch(git_path, module, remote, track_submodules, dest)
        if submodules_updated:
            result.update(submodules_changed=submodules_updated)
            if module.check_mode:
                result.update(changed=True, after=remote_head)
                module.exit_json(**result)
            
            submodule_update(git_path, module, dest, track_submodules, force=force)
    
    result['after'] = get_version(module, git_path, dest)
    if result['before'] != result['after'] or local_mods or submodules_updated or remote_url_changed:
        result.update(changed=True)
        if module._diff:
            diff = get_diff(module, git_path, dest, repo, remote, depth, bare, result['before'], result['after'])
            if diff:
                result['diff'] = diff
    if archive:
        
        
        if module.check_mode:
            result.update(changed=True)
            module.exit_json(**result)
        create_archive(git_path, module, dest, archive, archive_prefix, version, repo, result)
    module.exit_json(**result)
if __name__ == '__main__':
    main()