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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`


version_added: '2.11'
    track_submodules:
        description:
            - If C(yes), submodules will track the latest commit on their
              master branch (or other branch specified in .gitmodules).  If
              C(no), submodules will be kept at the revision specified by the
              main project. This is equivalent to specifying the --remote flag
              to git submodule update.
        type: bool
        default: 'no'
        version_added: "1.8"
    verify_commit:
        description:
            - If C(yes), when cloning or checking out a I(version) verify the
              signature of a GPG signed commit. This requires git version>=2.1.0
              to be installed. The commit MUST be signed and the public key MUST
              be present in the GPG keyring.
        type: bool
        default: 'no'
        version_added: "2.0"
    archive:
        description:
            - Specify archive file path with extension. If specified, creates an
              archive file of the specified format containing the tree structure
              for the source tree.
              Allowed archive formats ["zip", "tar.gz", "tar", "tgz"].
            - This will clone and perform git archive from local directory as not
              all git servers support git archive.
        type: path
        version_added: "2.4"