Testing and validation for object storage configuration

[viktor-f]

Description

The object storage configuration is currently quite complex. It is possible to use a few different types of object storage. For some components (harbor and thanos) you can override what object storage to use. You can sync or restore with rclone, with many possibilities to override defaults. The config is also spread out across the different config files and the secrets file.

We could look at simplifying the config, but that might be a lot of work. So Instead this task would focus on adding some tests and config validation. The tests should ensure that the config gets used in the intended way and the validation could ensure that you get warnings in case you missed some configuration that is needed for a particular setup.

Additional context

No response

Definition of done

• [ ] Unit tests are added to ensure that the config works as expected
• [ ] Config validation is added via the config schema to warn if something is missing or misconfigured.