fix: "Cluster connectivity setup" documentation errors

[mathieu-anderson]

Implementation of this feature surfaced a few issues with the " Cluster connectivity setup" section:

• incorrect application.properties values in https://www.klaw-project.io/docs/cluster-connectivity-setup/sr-cluster-ssl-protocol
• missing section for Kafka flavor "Apache Kafka" and cluster type "Kafka connect"
• occasional typos and misformatting (no code block, git commit message in code block)

These should be remedied.