Retrieves the passcode for the given user.
Audiohook will send an email to the provided email, with the login
passcode has a lifespan of 15 minutes.
If there is an issue you may get the following responses:
Cannot login without a company email - This user has been banned
User not found - This user does not exist
User is disabled - This user has been disabled
Could not send passcode - There was an issue on the Audiohook server
There was an error sending passcode - There was an issue on the Audiohook server
Email must be set - The email was missing from the request
This passcode then must be used to log in via a POST request to the
/signin endpoint in order to perform the Basic Authentication and retrieve the access token.