update list_email_content to DRF

[awais786]

Issue: #35112

existing API Code

Updating api code using DRF.

1. Added standard authentication_classes
2. Added permission_classes

Steps to verify on local tutor instance:
1: Open admin panel and laod this page and enable both checkboxes and save.
2: Open this page and enter course id and enabled email.
3. Open instructor dashboard.
4. email tab is visible and click on that and further click new experience.
5. Send an email email now.
6. Click on Email Task History now it will hit the related API.

Steps to verify via postman.

1. Pass the URL in postman.
2. Pass required csrf token and access token.

expected result

{
    "emails": [
        {
            "created": "2024-07-31T07:20:30.293Z",
            "sent_to": [
                "Myself"
            ],
            "requester": "admin",
            "email": {
                "subject": "awa",
                "html_message": "<p>aaaa</p>",
                "id": "2"
            },
            "number_sent": "1 sent"
        },
        {
            "created": "2024-07-31T07:17:50.419Z",
            "sent_to": [
                "Myself",
                "All students"
            ],
            "requester": "admin",
            "email": {
                "subject": "awais",
                "html_message": "<p>THis is not a <strong>ways</strong></p>",
                "id": "1"
            },
            "number_sent": "2 sent"
        }
    ]
}