### Apache Airflow version

2.6.3

### What happened

A task instance's [log_url](https://github.com/apache/airflow/blob/2.6.3/airflow/models/taskinstance.py#L726) does not contain the full URL defined in [base_url](https://github.com/apache/airflow/blob/2.6.3/airflow/models/taskinstance.py#L729C9-L729C69).

### What you think should happen instead

The base_url may contain paths that should be acknowledged when build the log_url. 

The log_url is built with [urljoin](https://docs.python.org/3/library/urllib.parse.html#urllib.parse.urljoin). Due to how urljoin builds URLs, any existing paths are ignored leading to a faulty URL. 

### How to reproduce

This snippet showcases how urljoin ignores existing paths when building the url.

```
>>> from urllib.parse import urljoin
>>> 
>>> 
>>> urljoin(
...     "https://my.astronomer.run/path",
...     f"log?execution_date=test"
...     f"&task_id=wow"
...     f"&dag_id=super"
...     f"&map_index=-1",
... )
'https://eochgroup.astronomer.run/log?execution_date=test&task_id=wow&dag_id=super&map_index=-1'
```

### Operating System

n/a

### Versions of Apache Airflow Providers

_No response_

### Deployment

Astronomer

### Deployment details

_No response_

### Anything else

This was introduced by #31833.

A way to fix this can be to utilize [urlsplit](https://docs.python.org/3/library/urllib.parse.html#urllib.parse.urlsplit) and [urlunsplit](https://docs.python.org/3/library/urllib.parse.html#urllib.parse.urlunsplit) to account for existing paths.

```
from urllib.parse import urlsplit, urlunsplit

parts = urlsplit("https://my.astronomer.run/paths")
urlunsplit((
        parts.scheme,
        parts.netloc,
        f"{parts.path}/log",
        f"execution_date=test"
        f"&task_id=wow"
        f"&dag_id=super"
        f"&map_index=-1",
        ""
    )
)
```

Here is the fix in action.

```
>>> parts = urlsplit("https://my.astronomer.run/paths")
>>> urlunsplit((
...     parts.scheme,
...     parts.netloc,
...     f"{parts.path}/log",
...     f"execution_date=test"
...     f"&task_id=wow"
...     f"&dag_id=super"
...     f"&map_index=-1",
...     ''))
'https://my.astronomer.run/paths/log?execution_date=test&task_id=wow&dag_id=super&map_index=-1'
>>>
>>> parts = urlsplit("https://my.astronomer.run/paths/test")
>>> urlunsplit((
...     parts.scheme,
...     parts.netloc,
...     f"{parts.path}/log",
...     f"execution_date=test"
...     f"&task_id=wow"
...     f"&dag_id=super"
...     f"&map_index=-1",
...     ''))
'https://my.astronomer.run/paths/test/log?execution_date=test&task_id=wow&dag_id=super&map_index=-1'
```

### Are you willing to submit PR?

- [ ] Yes I am willing to submit a PR!

### Code of Conduct

- [X] I agree to follow this project's [Code of Conduct](https://github.com/apache/airflow/blob/main/CODE_OF_CONDUCT.md)

if TYPE_CHECKING:
                        assert self.task.dag
                    execution_date = timezone.make_aware(execution_date, self.task.dag.timezone)
                else:
                    execution_date = timezone.make_aware(execution_date)
                execution_date = timezone.convert_to_utc(execution_date)
            with create_session() as session:
                run_id = (
                    session.query(DagRun.run_id)
                    .filter_by(dag_id=self.dag_id, execution_date=execution_date)
                    .scalar()
                )
                if run_id is None:
                    raise DagRunNotFound(
                        f"DagRun for {self.dag_id!r} with date {execution_date} not found"
                    ) from None
        self.run_id = run_id
        self.try_number = 0
        self.max_tries = self.task.retries
        self.unixname = getuser()
        if state:
            self.state = state
        self.hostname = ""
        
        
        self.raw = False
        
        self.test_mode = False
    @property
    def stats_tags(self) -> dict[str, str]: