Production sampling

[pandatix]

Current approach is to sample every trace generated by chall-manager. This is good for developing and debugging, but in reality this is not always interesting.

https://github.com/ctfer-io/chall-manager/blob/main/global/otel.go#L46-L49

OpenTelemetry documentation states the following.

When in a production environment, consider using the ParentBased sampler with the TraceIDRatioBased sampler.

Getting closer to GA, I think it becomes important to consider real production setups.