Create a Stripe seller account for the authenticated user and return the onboarding URL.
When a new seller account is created, a URL will be returned that the user should be forwarded to in order to complete the Stripe KYC/AML onboarding process.
If the user already has a seller account (this endpoint is idempotent), a new onboarding URL will be generated.
This endpoint requires to URLs to be provided in the request body:
returnUrl: The URL to redirect to after the onboarding is complete.refreshUrl: The URL to redirect to if the onboarding needs to be refreshed. Ie. the user went to make a coffee.Bearer authentication header of the form Bearer <token>, where <token> is your auth token.