curl --request GET \
  --url https://{cluster}.voucherify.io/management/v1/projects/{projectId}/custom-event-schemas \
  --header 'X-Management-Id: <api-key>' \
  --header 'X-Management-Token: <api-key>'

{
  "object": "list",
  "data_ref": "data",
  "data": [
    {
      "id": "ms_t4ir0Dcu5T0m3v3nT5ch3ma",
      "name": "newsletter_subscribed",
      "schema": {
        "properties": {}
      },
      "created_at": "2023-08-03T10:37:48.716Z",
      "object": "custom-event-schema"
    },
    {
      "id": "ms_s3c0N6cu5T0m3v3nT5ch3ma",
      "name": "review_left",
      "schema": {
        "properties": {}
      },
      "created_at": "2023-08-03T10:37:48.710Z",
      "updated_at": "2024-04-26T14:35:03.463Z",
      "object": "custom-event-schema"
    },
    {
      "id": "ms_f1r5Tcu5T0m3v3nT5ch3ma",
      "name": "sign_up",
      "schema": {
        "properties": {}
      },
      "created_at": "2023-08-03T10:37:48.705Z",
      "object": "custom-event-schema"
    }
  ],
  "total": 3
}