Verify phone number

curl --request POST \
  --url {schemes}://api.upsun.com/users/{user_id}/phonenumber \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "channel": "sms",
  "phone_number": "<string>"
}
'

{
  "sid": "<string>"
}