### Apache Airflow version

2.1.2

### What happened

Task duration view for triggered dags shows all dag runs instead of n last. Changing the number of runs in the `Runs` drop-down menu doesn't change the view. Additionally the chart loads slowly, it show all dag runs.

![screenshot_2022-03-05_170203](https://user-images.githubusercontent.com/7863204/156891332-5e461661-970d-49bf-82a8-5dd1da57bb02.png)
 

### What you expected to happen

The number of shown dag runs is 25 (like for scheduled dags), and the last runs are shown. The number of runs button should allow to increase / decrease the number of shown dag runs (respectively the task times of the dag runs).

### How to reproduce

Trigger a dag multiple (> 25) times. Look at the "Task Duration" chart.

### Operating System

Linux

### Versions of Apache Airflow Providers

_No response_

### Deployment

Official Apache Airflow Helm Chart

### Deployment details

_No response_

### Anything else

_No response_

### 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)

self,
        last_automated_dagrun: None | datetime | DataInterval,
        *,
        restricted: bool = True,
    ) -> DagRunInfo | None:
        """Get information about the next DagRun of this dag after ``date_last_automated_dagrun``.
        This calculates what time interval the next DagRun should operate on
        (its execution date) and when it can be scheduled, according to the
        dag's timetable, start_date, end_date, etc. This doesn't check max
        active run or any other "max_active_tasks" type limits, but only
        performs calculations based on the various date and interval fields of
        this dag and its tasks.
        :param last_automated_dagrun: The ``max(execution_date)`` of
            existing "automated" DagRuns for this dag (scheduled or backfill,
            but not manual).
        :param restricted: If set to *False* (default is *True*), ignore
            ``start_date``, ``end_date``, and ``catchup`` specified on the DAG
            or tasks.
        :return: DagRunInfo of the next dagrun, or None if a dagrun is not
            going to be scheduled.
        """
        
        if self.is_subdag:
            return None