List regions

curl --request GET \
  --url {schemes}://api.upsun.com/regions \
  --header 'Authorization: Bearer <token>'

{
  "count": 123,
  "regions": [
    {
      "id": "<string>",
      "label": "<string>",
      "zone": "<string>",
      "selection_label": "<string>",
      "project_label": "<string>",
      "timezone": "<string>",
      "available": true,
      "private": true,
      "endpoint": "<string>",
      "provider": {
        "name": "<string>",
        "logo": "<string>"
      },
      "datacenter": {
        "name": "<string>",
        "label": "<string>",
        "location": "<string>"
      },
      "environmental_impact": {
        "zone": "<string>",
        "carbon_intensity": "<string>",
        "green": true
      }
    }
  ],
  "_links": {
    "self": {
      "href": "<string>"
    },
    "previous": {
      "href": "<string>"
    },
    "next": {
      "href": "<string>"
    }
  }
}