Get Qt account ID from Qt account login API (write an API for this)

When we login to the Qt account APi via the username, password - there is another API to get CONAN username and password. This conan username is actaully the "ACCOUNT ID" of the QT account customer. We should find out ways how we can only get this "ACCOUNT ID" when the login is successful. 

AFAIR, this "ACCOUNT ID" is just the "Primary key" of the database for the Qt account user. And we wil use this - because this cannot be used to identify the user personally.