[kong] add cluster telemetry service

[rainest]

What this PR does / why we need it:

• Add support for the cluster telemetry service. This service is similar to the cluster service, but is used to ship Vitals data from Enterprise DP nodes.

Which issue this PR fixes

• fixes [kong] readme error #184 (minor doc rollup fix unrelated to the main PR)
• fixes an issue reported internally, where DP nodes with Vitals enabled would complain about cluster service failures. These are in fact cluster telemetry service failures, and do not interfere with the main cluster service. Inbound core changes will make those error reports less confusing, as they will indicate the specific failing endpoint.

Special notes for your reviewer:

• Also adds a cluster port to the deployment. It was previously omitted, and while omitting it doesn't break communication, it does misreport things (the port was open, but not declared).
• The Service name is too long for port names, so this uses a shortened clustert-tls name in the Deployment, whereas most stuff uses clustertelemetry-tls
• We don't currently have automated hybrid tests. At present, the hybrid namespace on our test cluster contains a pair of silly-rabbit releases that have Enterprise CP/DP nodes that share configuration and Vitals data.

Checklist

[Place an '[x]' (no spaces) in all applicable fields. Please remove unrelated fields.]

• PR is based off the current tip of the next branch and targets next, not main
• New or modified sections of values.yaml are documented in the README.md
• Title of the PR and commit headers start with chart name (e.g. [kong])

[hbagdi]

cluster is a horrible name but it is what it is in this case.