Logging not working correctly for gunicorn or user logs

Description

Gunicorn - logs not structured (likely needs fix in ucam-observe as well, going to back to using the magic named dictionary but sourced from a common set of configutation)

General application logs - seems to be double json encoded with the "event" of the json payload being a json encoded string. Most likely conflicts between the ucam-observe "just works" and the original log setup. Only ucam-faas unique code should be in this repo, general flask wiring code should be in ucam-observe

Acceptance criteria

• deployed gunicorn logs are structure
• deployed application logs are correctly structured and not double json encoded