If the organisation name that is being inserted or updated is not unique we just want to return a 400 to the admin app.
Updated the code so that we are not logging.exception, this is because a cloud watch alert is set to the support team. This type of error is not something we need to investigate.
- Changed the organisation DAO update method to only make 1 query
- Updated the update rest endpoint to not return an organisation when
the update is successful
notable things that have been kept until migration is complete:
* passing in `organisation` to update_service will update email branding
* both `/email-branding` and `/organisation` hit the same code
* service endpoints still return organisation as well as email branding