### 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)

delay_backoff_in_seconds = min(modded_hash, MAX_RETRY_DELAY)
            delay = timedelta(seconds=delay_backoff_in_seconds)
            if self.task.max_retry_delay:
                delay = min(self.task.max_retry_delay, delay)
        return self.end_date + delay
    def ready_for_retry(self) -> bool:
        """Checks on whether the task instance is in the right state and timeframe to be retried."""
        return self.state == TaskInstanceState.UP_FOR_RETRY and self.next_retry_datetime() < timezone.utcnow()
    @provide_session
    def get_dagrun(self, session: Session = NEW_SESSION) -> DagRun:
        """
        Returns the DagRun for this TaskInstance.
        :param session: SQLAlchemy ORM Session
        :return: DagRun
        """
        info = inspect(self)
        if info.attrs.dag_run.loaded_value is not NO_VALUE:
            if hasattr(self, "task"):
                self.dag_run.dag = self.task.dag
            return self.dag_run
        from airflow.models.dagrun import DagRun  
        dr = session.query(DagRun).filter(DagRun.dag_id == self.dag_id, DagRun.run_id == self.run_id).one()
        if hasattr(self, "task"):
            dr.dag = self.task.dag
        
        set_committed_value(self, "dag_run", dr)
        return dr
    @provide_session
    def check_and_change_state_before_execution(