如何修复我的Heroku Web挂钩“ missing_text_or_fallback_or_attachments”中的错误

Question

我想在闲暇时收到有关我的heroku服务器进程（例如dyno restart等）的通知。我尝试实现heroku的webhook应用程序，但遇到“ missing_text_or_fallback_or_attachments”错误。

我传入的Slack的Webhook URL可以100％工作，因为我尝试使用该Webhook URL发送消息。

这是我的有效载荷

    {
    "action": "update",
    "actor": {
        "email": "pvbarredo@gmail.com",
        "id": "05abb58b-178d-4d2a-9d02-a6e951b7badf"
    },
    "created_at": "2019-06-12T07:04:17.482868Z",
    "data": {
        "addon_plan_names": [
            "jawsdb-maria:kitefin"
        ],
        "app": {
            "id": "dc0b5699-fb76-4509-98ca-810c40710cca",
            "name": "opi-recognition"
        },
        "created_at": "2019-06-12T07:04:17Z",
        "current": true,
        "description": "Remove webhook_secret config vars",
        "id": "f291cd03-2e81-47fd-a3f9-c8c8120a8d81",
        "output_stream_url": null,
        "pstable": {
            "web": {
                "command": "java -Dserver.port=$PORT -jar build/libs/recognition-0.0.1-SNAPSHOT.jar",
                "slug": {
                    "id": "827f9c32-2417-427f-8d08-93dd7b07a84e"
                }
            }
        },
        "slug": {
            "id": "827f9c32-2417-427f-8d08-93dd7b07a84e",
            "commit": "de6c860652a207f6f0e78ef5723279b962924aef",
            "commit_description": ""
        },
        "status": "succeeded",
        "updated_at": "2019-06-12T07:04:17Z",
        "user": {
            "email": "pvbarredo@gmail.com",
            "id": "05abb58b-178d-4d2a-9d02-a6e951b7badf"
        },
        "version": 25
    },
    "id": "8026b408-93de-4a7f-a0e8-94c1981b0f87",
    "previous_data": {},
    "published_at": "2019-06-12T07:04:17Z",
    "resource": "release",
    "sequence": null,
    "updated_at": "2019-06-12T07:04:17.482875Z",
    "version": "application/vnd.heroku+json; version=3",
    "webhook_metadata": {
        "attempt": {
            "id": "39200100-cd08-4262-9a0b-34145e485118"
        },
        "delivery": {
            "id": "dd755fcf-e166-4628-b6c4-de36a32a558e"
        },
        "event": {
            "id": "8026b408-93de-4a7f-a0e8-94c1981b0f87",
            "include": "api:release"
        },
        "webhook": {
            "id": "92e7ef01-be4e-4218-b484-5e026d140f68"
        }
    }
}  

我希望它应该能正常工作，因为我所做的只是挂上钩子，让heroku服务执行其任务。