Describe how to integrate krakend as a part of KubeRocketCI platform

[alezander86]

Create a document that outlines the integration of KrakenD into KubeRocketCI as an API gateway. This document should cover the following:

1. Purpose: Explain how KrakenD acts as a secure API gateway, forwarding tokens (e.g., for SonarQube and Dependency-Track) without exposing them to the client, thereby preventing unauthorized access to backend services.

2. Prerequisites: Detail the need for an ingress controller on the cluster and how to install it using resources from the Cluster Add-Ons repository.

3. Installation Guide: Provide steps to install KrakenD using resources from the Cluster Add-Ons repository to ensure efficient integration with the infrastructure.

4. Configuration Instructions: Describe how to configure the apiGatewayUrl in the values.yaml file for KubeRocketCI to set up KrakenD as the API gateway, noting that widgets are disabled if this URL is not provided.

5. Secret Management: Include steps to configure required secrets, including:

6. URLs and tokens for SonarQube and Dependency-Track.

7. The JWK URL for Keycloak integration.

8. Guidance on generating tokens in base64 format.

9. External Secrets Operator Integration: Provide example JSON configurations for managing external secrets (e.g., SonarQube URL, token, Dependency-Track URL, token, JWK URL).