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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`


archive_prefix:
        description:
            - Specify a prefix to add to each file path in archive. Requires I(archive) to be specified.
        version_added: "2.10"
        type: str
    separate_git_dir:
        description:
            - The path to place the cloned repository. If specified, Git repository
              can be separated from working tree.
        type: path
        version_added: "2.7"
    gpg_whitelist:
        description:
           - A list of trusted GPG fingerprints to compare to the fingerprint of the
             GPG-signed commit.
           - Only used when I(verify_commit=yes).
           - Use of this feature requires Git 2.6+ due to its reliance on git's C(--raw) flag to C(verify-commit) and C(verify-tag).
        type: list
        elements: str
        default: []
        version_added: "2.9"
requirements:
    - git>=1.7.1 (the command line tool)
attributes:
    check_mode:
        support: full
    diff_mode:
        support: full
    platform:
        platforms: posix