**Description**
In the trigger page, there is a text area to enter (optional) conf json. It would be great if a sample JSON can be provided programatically while defining DAG

**Use case / motivation**

This will improve usability of the UI that triggers a DAG

airflow/www/views.py
'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 View.
    """
    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,
            },
        }
    children = [
        task_group_to_dict(child) for child in sorted(task_group.children.values(), key=lambda t: t.label)
    ]
    if task_group.upstream_group_ids or task_group.upstream_task_ids:
        children.append(
            {
                'id': task_group.upstream_join_id,
                'value': {
                    'label': '',
                    'labelStyle': f"fill:{task_group.ui_fgcolor};",
                    'style': f"fill:{task_group.ui_color};",
                    'shape': 'circle',