Add authorization in webhook

[qornanali]

In order to prevent malicious requests, please modify the current webhook URL.

From /webhook to /v1/external/messenger/webhook?access_token=<access_token> where access_token is configurable from ENV for now.

Example curl

curl --location --request POST 'https://localhost:3000/external/messenger/v1/webhook?access_token=foo' \
--header 'Content-Type: application/json' \
--data-raw '{
    "object": "page",
    "entry": [
        {
            "id": "107461401142256",
            "time": 1602923843364,
            "messaging": [
                {
                    "sender": {
                        "id": "3394010770691329"
                    },
                    "recipient": {
                        "id": "107461401142256"
                    },
                    "timestamp": 1602923843223,
                    "message": {
                        "mid": "m_sFrBBrkrx2LmF8YZSBf7WeqfkEM-NXTTk34MVB5g2wYZUTOUt4RRD2EWhrrCyy4O86A6bj4NfeKid_R2johmBA",
                        "text": "kartu prakerja",
                        "nlp": {
                            "intents": [
                                {
                                    "id": "653269161996408",
                                    "name": "Tanya_program",
                                    "confidence": 0.9
                                }
                            ],
                            "entities": {
                                "nama_program:nama_program": [
                                    {
                                        "id": "387471645725440",
                                        "name": "nama_program",
                                        "role": "nama_program",
                                        "start": 0,
                                        "end": 14,
                                        "body": "kartu prakerja",
                                        "confidence": 0.9566,
                                        "entities": [],
                                        "value": "Kartu Prakerja",
                                        "type": "value"
                                    }
                                ]
                            },
                            "traits": {
                                "wit$sentiment": [
                                    {
                                        "id": "5ac2b50a-44e4-466e-9d49-bad6bd40092c",
                                        "value": "neutral",
                                        "confidence": 0.536
                                    }
                                ]
                            },
                            "detected_locales": [
                                {
                                    "locale": "id_ID",
                                    "confidence": 0.9685
                                }
                            ]
                        }
                    }
                }
            ]
        }
    ]
}'

If the incoming request has a blank access_token or incorrect, it should response with body:

FAILED

and http status 401 unauthorized.