### Apache Airflow version

2.1.3 (latest released)

### Operating System

macOS Big Sur 11.3.1

### Versions of Apache Airflow Providers

n/a

### Deployment

Astronomer

### Deployment details

default Astronomer deployment with some test DAGs

### What happened

In the UI for DAGRuns there are checkboxes that allow multiple DAGRuns to be selected.

![image](https://user-images.githubusercontent.com/89415310/133841290-94cda771-9bb3-4677-8530-8c2861525719.png)

Within the Actions menu on this same view, there is a Delete option which allows multiple DAGRuns to be deleted at the same time.

![image](https://user-images.githubusercontent.com/89415310/133841362-3c7fc81d-a823-4f41-8b1d-64be425810ce.png)

Task instance view on the UI does not offer the same option, even though Task Instances can be individually deleted with the trash can button.

![image](https://user-images.githubusercontent.com/89415310/133841442-3fee0930-a6bb-4035-b172-1d10b85f3bf6.png)


### What you expected to happen

I expect that the Task Instances can also be bulk deleted, in the same way that DAGRuns can be.

### How to reproduce

Open up Task Instance and DAGRun views from the Browse tab and compare the options in the Actions dropdown menus.

### Anything else

_No response_

### Are you willing to submit PR?

- [X] 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)

airflow/www/views.py
dr_state = dr.state
    
    if not dr_state and drs:
        dr = drs[0]
        date_time = dr.execution_date
        dr_state = dr.state
    return {
        'dttm': date_time,
        'base_date': base_date,
        'num_runs': num_runs,
        'execution_date': date_time.isoformat(),
        'dr_choices': dr_choices,
        'dr_state': dr_state,
    }
def task_group_to_dict(task_group):
    """
    Create a nested dict representation of this TaskGroup and its children used to construct
    the Graph.
    """
    if isinstance(task_group, BaseOperator):
        return {
            'id': task_group.task_id,
            'value': {
                'label': task_group.label,
                'labelStyle': f"fill:{task_group.ui_fgcolor};",
                'style': f"fill:{task_group.ui_color};",
                'rx': 5,
                'ry': 5,
            },
        }