Create a payment session

Creates a payment session for [Web Drop-in](https://docs.adyen.com/online-payments/web-drop-in) and [Web Components](https://docs.adyen.com/online-payments/web-components) integrations. The response contains encrypted payment session data. The front end then uses the session data to make any required server-side calls for the payment flow. You get the payment outcome asynchronously, in an [AUTHORISATION](https://docs.adyen.com/api-explorer/#/Webhooks/latest/post/AUTHORISATION) webhook.