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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`


notes:
    - "If the task seems to be hanging, first verify remote host is in C(known_hosts).
      SSH will prompt user to authorize the first contact with a remote host.  To avoid this prompt,
      one solution is to use the option accept_hostkey. Another solution is to
      add the remote host public key in C(/etc/ssh/ssh_known_hosts) before calling
      the git module, with the following command: ssh-keyscan -H remote_host.com >> /etc/ssh/ssh_known_hosts."
'''
EXAMPLES = '''
- name: Git checkout
  ansible.builtin.git:
    repo: 'https://foosball.example.org/path/to/repo.git'
    dest: /srv/checkout
    version: release-0.22
- name: Read-write git checkout from github
  ansible.builtin.git:
    repo: git@github.com:mylogin/hello.git
    dest: /home/mylogin/hello
- name: Just ensuring the repo checkout exists
  ansible.builtin.git:
    repo: 'https://foosball.example.org/path/to/repo.git'
    dest: /srv/checkout
    update: no
- name: Just get information about the repository whether or not it has already been cloned locally
  ansible.builtin.git:
    repo: 'https://foosball.example.org/path/to/repo.git'
    dest: /srv/checkout
    clone: no
    update: no
- name: Checkout a github repo and use refspec to fetch all pull requests
  ansible.builtin.git: