Create account invitation

curl --request POST \
  --url https://cookiechimp.com/api/v1/account-invitations \
  --header 'Authorization: <api-key>' \
  --header 'Content-Type: application/json' \
  --data '{
  "name": "<string>",
  "email": "jsmith@example.com",
  "role": "admin"
}'

{
  "id": "inv123",
  "email": "newmember@cookiechimp.com",
  "role": "member",
  "invited_by_type": "API",
  "created_at": "2023-01-25T09:30:20Z",
  "updated_at": "2023-01-25T09:30:20Z"
}