[Maintenance] Replace unmaintained Bitnami Legacy images with free SolDevelo alternative

[igor-soldev]

Hi team!

I noticed that examples/http.kafka.oneway/compose.yaml uses bitnamilegacy/kafka for both the broker and the init container. Since the "legacy" repository is effectively frozen (no security updates), I suggest switching to soldevelo/kafka (maintained by my team). Link: https://hub.docker.com/r/soldevelo/kafka

It is free to use, actively updated, and works as a drop-in replacement. It will work seamlessly for both the main service and the kafka-init job without any config changes.

I can submit a quick PR to update this if you're interested!