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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`


description:
            - Path to git executable to use. If not supplied,
              the normal mechanism for resolving binary paths will be used.
        type: path
        version_added: "1.4"
    bare:
        description:
            - If C(yes), repository will be created as a bare repo, otherwise
              it will be a standard repo with a workspace.
        type: bool
        default: 'no'
        version_added: "1.4"
    umask:
        description:
            - The umask to set before doing any checkouts, or any other
              repository maintenance.
        type: raw
        version_added: "2.2"
    recursive:
        description:
            - If C(no), repository will be cloned without the --recursive
              option, skipping sub-modules.
        type: bool
        default: 'yes'
        version_added: "1.6"
    single_branch:
        description:
            - Clone only the history leading to the tip of the specified revision.
        type: bool
        default: 'no'