**Apache Airflow version**: 2.1.0

**Browsers**: Chrome and Firefox

**What happened**:

Before upgrading to 2.1.0

![before](https://user-images.githubusercontent.com/14293802/120359517-c1ca1100-c2d5-11eb-95ba-58ccc0a3ac37.png)

After upgrading to 2.1.0

![after](https://user-images.githubusercontent.com/14293802/120359528-c4c50180-c2d5-11eb-8e04-f34846ea2736.png)

**What you expected to happen**:

Show/Edit/Delete under Security -> Users are available

<!-- What do you think went wrong? -->

**How to reproduce it**:

Go to Security -> Users (as an admin of course) 
airflow/www/views.py
'description',
        'host',
        'port',
        'is_encrypted',
        'is_extra_encrypted',
    ]
    add_columns = edit_columns = [
        'conn_id',
        'conn_type',
        'description',
        'host',
        'schema',
        'login',
        'password',
        'port',
        'extra',
    ] + extra_fields
    add_form = edit_form = ConnectionForm
    add_template = 'airflow/conn_create.html'
    edit_template = 'airflow/conn_edit.html'
    add_widget = ConnectionFormWidget
    edit_widget = ConnectionFormWidget
    base_order = ('conn_id', 'asc')
    @action('muldelete', 'Delete', 'Are you sure you want to delete selected records?', single=False)
    @auth.has_access(
        [
            (permissions.ACTION_CAN_EDIT, permissions.RESOURCE_DAG),
        ]
    )
    def action_muldelete(self, items):