### 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
version_added: "1.6"
    single_branch:
        description:
            - Clone only the history leading to the tip of the specified revision.
        type: bool
        default: 'no'
        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