curl --request POST \
  --url https://{tenant_id}.hanko.io/users \
  --header 'Content-Type: application/json' \
  --data '{
  "email": "jsmith@example.com"
}'

{
  "user_id": "c339547d-e17d-4ba7-8a1d-b3d5a4d17c1c",
  "email_id": "c339547d-e17d-4ba7-8a1d-b3d5a4d17c1c"
}