[deployed] Support specifying the logging mode

Problem to Solve

We're building the Knowledge Graph to be a deployable service which can be hosted in .com but also in self-managed environment. This means that our observability setup must comply with what's already in place as much as possible, while also giving some flexibility for customers.

One thing that comes to mind is that, currently, logging for the deployed http-server is only done by writing logs to stdout/stderr. Some customers might not use k8s or an alternative that supports directly flushing logs to log collectors (such as ElasticSearch).

We need to give flexibility to customers on how they want their logging to work

Proposed Solution

Create a flexible logging configuration which allows to specify:

• The log level
• The log format
• The log destination (files, stdout/stderr)