### Summary

See: https://github.com/ansible/ansible/blob/devel/lib/ansible/modules/git.py#L760 :

```py
            repo_path = os.path.join(repo_path.split('.git')[0], gitdir)
```

the intention of this code seems to be to strip `.git` from the end of the path.

If the repo path contains `.git` anywhere, like `/tmp/music.gittern/myrepo`, tasks will unexpectedly fail:

```
fatal: [localhost]: FAILED! => {"changed": false, "details": "/tmp/music/../.git/modules/submodule is not a directory", "msg": "Current repo does not have a valid reference to a separate Git dir or it refers to the invalid path"}
```

For a playbook like:
```yaml
---
- hosts: localhost
  tasks:
   - name: test git
     git: 
        repo: ...
        dest: /tmp/music.gittern/myrepo/submodule
```

I can't tell if this is a potential security issue or just an unexpected corner case. What I am pretty sure I can tell, is that that's not how one strips `.git` from the end of a path.

### Issue Type

Bug Report

### Component Name

git

### Ansible Version

```console
$ ansible --version
2.11
```


### Configuration

```console
$ ansible-config dump --only-changed
ANSIBLE_NOCOWS(/home/enrico/dev/transilience/ansible.cfg) = True
```


### OS / Environment

Debian Bullseye

### Steps to Reproduce

Use submodules in a repo whose path contains `.git` anywhere as part of a file name.
For example:
```yaml
---
- hosts: localhost
  tasks:
   - name: test git
     git: 
        repo: ...
        dest: /tmp/music.gittern/myrepo/submodule
```

### Expected Results

I'd expect directory names like `gato.gito` not to be interpreted specially by mistake

### Actual Results

```console
fatal: [localhost]: FAILED! => {"changed": false, "details": "/tmp/music/../.git/modules/submodule is not a directory", "msg": "Current repo does not have a valid reference to a separate Git dir or it refers to the invalid path"}
```


### Code of Conduct

- [X] I agree to follow the Ansible Code of Conduct
default: 'no'
        version_added: "2.12"
    ssh_opts:
        description:
            - Creates a wrapper script and exports the path as GIT_SSH
              which git then automatically uses to override ssh arguments.
              An example value could be "-o StrictHostKeyChecking=no"
              (although this particular option is better set by
              I(accept_hostkey)).
        type: str
        version_added: "1.5"
    key_file:
        description:
            - Specify an optional private key file path, on the target host, to use for the checkout.
        type: path
        version_added: "1.5"
    reference:
        description:
            - Reference repository (see "git clone --reference ...").
        version_added: "1.4"
    remote:
        description:
            - Name of the remote.
        type: str
        default: "origin"
    refspec:
        description:
            - Add an additional refspec to be fetched.
              If version is set to a I(SHA-1) not reachable from any branch
              or tag, this option may be necessary to specify the ref containing