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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`


from __future__ import absolute_import, division, print_function
__metaclass__ = type
DOCUMENTATION = '''
---
module: git
author:
    - "Ansible Core Team"
    - "Michael DeHaan"
version_added: "0.0.1"
short_description: Deploy software (or files) from git checkouts
description:
    - Manage I(git) checkouts of repositories to deploy files or software.
extends_documentation_fragment: action_common_attributes
options:
    repo:
        description:
            - git, SSH, or HTTP(S) protocol address of the git repository.
        type: str
        required: true
        aliases: [ name ]
    dest:
        description:
            - The path of where the repository should be checked out. This
              is equivalent to C(git clone [repo_url] [directory]). The repository
              named in I(repo) is not appended to this path and the destination directory must be empty. This
              parameter is required, unless I(clone) is set to C(no).