Add documentation about how to use KIC with cert-manager

[tao12345666333]

Is there an existing issue for this?

• I have searched the existing issues

Does this enhancement require public documentation?

• I have added an Acceptance Criteria item for adding and/or adjusting public documentation (if applicable)

Problem Statement

Currently, we have an integration of cert-manager in the Helm chart, but it is not intended for proxying external traffic.

https://github.com/Kong/charts/tree/main/charts/kong#cert-manager-integration

We need a guide, similar to the "Get started" document so that users can easily integrate KIC with the cert-manager.

Proposed Solution

No response

Additional information

No response

Acceptance Criteria

• Write an article about integrating and using KIC and cert-manager. Describe how to install and deploy them, and configure certificate access through Ingress or gateway API.

[lahabana]

Deferring until the new docs site is online as it will fit much better there.