In preparation for moving the SNS notification to an SES queue remove
the HTTP errors codes and arguments as the method will now be run by
a celery task. Also made the callback http method return more generic
codes as this will be removed in the longer term.
- Removed errors and arguments returned from process_ses_response
- Updated tests
There are three authentication methods:
- requires_no_auth - public endpoint that does not require an Authorisation header
- requires_auth - public endpoints that need an API key in the Authorisation header
- requires_admin_auth - private endpoint that requires an Authorisation header which contains the API key for the defined as the client admin user
