List email templates

curl --request GET \
  --url https://api.kit.com/v4/email_templates \
  --header 'X-Kit-Api-Key: <api-key>'

{
  "email_templates": [
    {
      "id": 69,
      "name": "Custom HTML Template",
      "is_default": false,
      "category": "HTML"
    },
    {
      "id": 68,
      "name": "Story",
      "is_default": false,
      "category": "Starting point"
    },
    {
      "id": 6,
      "name": "Text Only",
      "is_default": true,
      "category": "HTML"
    },
    {
      "id": 4,
      "name": "Modern",
      "is_default": false,
      "category": "HTML"
    },
    {
      "id": 2,
      "name": "Classic",
      "is_default": false,
      "category": "HTML"
    },
    {
      "id": 1,
      "name": "Card",
      "is_default": false,
      "category": "HTML"
    }
  ],
  "pagination": {
    "has_previous_page": false,
    "has_next_page": false,
    "start_cursor": "WzY5XQ==",
    "end_cursor": "WzFd",
    "per_page": 500
  }
}