Verify email of the root user

The second step in verifying the root user's email. The randomly generated code sent to the root user via email, using the consumerRootUserEmailVerificationCodeSend operation, is submitted here to verify the root user's email.

This is needed as part of the verification process for basic due diligence.

Note that on the Sandbox Environment, emails are not sent and the verification code is always set to "123456".