[helm] Allow templating listeners (internal, client) from values

[morazow]

Purpose

Linked issue: close #2459

Brief change log

Adds templating for listeners in the values file

Tests

NA

API and Format

NA

Documentation

Updated for listeners configuration options.

[affo]

Thank you!
Multiple comments added.

I would also add, that it would also be nice to also configure the security protocol map as part of this PR.
As we would allow to template listeners, one can decide for the port, as well as the security protocol.

[morazow]

Thanks @affo, I have addressed your findings.

I will introduce the external access support in the follow up PR.

For the security map, let's discuss it once we have PR for enabling security (e.g, SASL) protocol in the helm charts 🤝

[affo]

Thank you!
Good to go for me 🤝

For the security protocol, @morazow can you please follow up with a PR before the external connection?
Ideally any external connection should specify some security criteria 🤝