Fix: Acutally validate config struct

[simonswine]

We seem to have not linked up the validation for a few components.

[marcsanmi]

LGTM 👍

[kolesnikovae]

This might be a breaking change. Does it make sense to add a flag that enables/disables config validation?

[julienvey]

I think we hit this breaking change.

We were using a storage_prefix value for s3 storage (the bucket is shared for multiple application / envs)

storage_prefix: pyroscope/my-env/

and this is now failing on the latest versions of Pyroscope

failed creating pyroscope: storage prefix contains invalid characters, it may only contain digits and English alphabet letters

I see the code for regex validation has been there for more than 3 years

storage_prefix with a / has been working fine so far, I don't really see a reason why / or - should be excluded.

Is there any workaround for us to keep the current storage prefix ? Otherwise we would need to set up a new one without the /, and we would either loose all existing data, or would need to move it for all environments