List retrospective configurations

curl --request GET \
  --url https://api.rootly.com/v1/retrospective_configurations \
  --header 'Authorization: Bearer <token>'

{
  "data": [
    {
      "id": "<string>",
      "type": "retrospective_configurations",
      "attributes": {
        "kind": "skip",
        "severity_ids": [
          "<string>"
        ],
        "group_ids": [
          "<string>"
        ],
        "incident_type_ids": [
          "<string>"
        ],
        "created_at": "<string>",
        "updated_at": "<string>"
      }
    }
  ]
}