### Description

In Airflow UI. If we go to Browse --> DAG Runs, then DAG Runs view will be displayed.

Table contains a lot of insightful values likes DAG execution date, Start date, end date, Dag config etc

Request to add DAG duration column in the same table.
DAG Duration i.e. DAG end_date timestamp  - DAG start_date timestamp

### Use case/motivation

Analytics purpose of knowing DAG duration at all DAGs level. So that I can easily find out which DAG  have least and max duration.

### Related issues

Checked open issues. There aren't any

### Are you willing to submit a 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)

airflow/www/views.py
"""Customize permission names for FAB's builtin ResetPasswordView."""
    class_permission_name = permissions.RESOURCE_PASSWORD
    method_permission_name = {
        'this_form_get': 'read',
        'this_form_post': 'edit',
    }
    base_permissions = [permissions.ACTION_CAN_EDIT, permissions.ACTION_CAN_READ]
class CustomRoleModelView(RoleModelView):
    """Customize permission names for FAB's builtin RoleModelView."""
    class_permission_name = permissions.RESOURCE_ROLE
    method_permission_name = {
        'delete': 'delete',
        'download': 'read',
        'show': 'read',
        'list': 'read',
        'edit': 'edit',
        'add': 'create',
        'copy_role': 'create',
    }
    base_permissions = [
        permissions.ACTION_CAN_CREATE,
        permissions.ACTION_CAN_READ,
        permissions.ACTION_CAN_EDIT,
        permissions.ACTION_CAN_DELETE,
    ]
class ResourceModelView(ViewMenuModelView):