### Summary

when running ansible-test over a collection, if there are errors or failures, it will link you to the correct documentation to help resolve the issue. this functionality is currently broken as it is linking to `docs.ansible.com/ansible/` instead of `docs.ansible.com/ansible-core/` which leads to 404s. 


### Issue Type

Bug Report

### Component Name

ansible-test

### Ansible Version

```console
$ ansible --version
ansible [core 2.11.2]
```


### Configuration

```console
$ ansible-config dump --only-changed
```


### OS / Environment

Fedora 34

### Steps to Reproduce

<!--- Paste example playbooks or commands between quotes below -->
```yaml (paste below)
ansible-test sanity --docker
```


### Expected Results

Expect for docs link to correct navigate to the correct documentation. 

### Actual Results

```console
leads to documentation that 404s. Ex: https://docs.ansible.com/ansible/2.12/dev_guide/testing/sanity/pylint.html
```


### Code of Conduct

- [X] I agree to follow the Ansible Code of Conduct
"""Write results to a junit XML file."""
        test_case = junit_xml.TestCase(
            classname=self.command,
            name=self.name,
            skipped=self.reason or 'No tests applicable.',
        )
        self.save_junit(args, test_case)
class TestFailure(TestResult):
    """Test failure."""
    def __init__(
            self,
            command,  
            test,  
            python_version=None,  
            messages=None,  
            summary=None,  
    ):
        super().__init__(command, test, python_version)
        if messages:
            messages = sorted(messages)
        else:
            messages = []
        self.messages = messages
        self.summary = summary
    def write(self, args):