docs(helm): add documentation about installation and external databas…

[leofvo]

Hello,

After installing the helm chart and set up an external database connection, I feel like it's a bit tricky, and we could make it more straight forward with a little documentation.

So I wrote the documentation from my own experience installing the helm chart and set up an external database.

Feel free to give feedback.

[dryrunsecurity]

DryRun Security Summary

The pull request primarily focuses on updating the documentation for the DefectDojo application's Kubernetes deployment, including changes to the Helm repository URL, instructions for using an external PostgreSQL database, and expanded documentation for high availability deployment, TLS configuration, and Prometheus metrics, which promote more secure and reliable deployment practices.

Expand for full summary

Summary:

The changes in this pull request primarily focus on updating the documentation for the DefectDojo application's Kubernetes deployment. The key changes include:

1. Updating the Helm repository URL and chart version/app version.
2. Providing instructions for using an external PostgreSQL database, including the creation of a Kubernetes secret to store the database credentials.
3. Expanding the documentation for high availability deployment, TLS configuration, and Prometheus metrics.

From an application security perspective, these changes are positive as they promote more secure and reliable deployment practices. The use of an external PostgreSQL database and the creation of a Kubernetes secret for storing credentials are good security practices. Additionally, the expanded documentation for high availability and monitoring will help ensure the overall security and stability of the deployed application.

Files Changed:

1. helm/defectdojo/README.md: The contents of this file have been replaced with a link to the KUBERNETES.md file, which contains the updated Kubernetes deployment documentation.
2. helm/defectdojo/.helmignore: The README.md file has been added to the list of files to be ignored when building the Helm package.
3. readme-docs/KUBERNETES.md: This file has been updated with the changes described in the summary, including instructions for using an external PostgreSQL database, high availability deployment, TLS configuration, and Prometheus metrics.

Code Analysis

We ran 9 analyzers against 4 files and 0 analyzers had findings. 9 analyzers had no findings.

Riskiness

🟢 Risk threshold not exceeded.

View PR in the DryRun Dashboard.

[kiblik]

It might be better to place it into https://github.com/DefectDojo/django-DefectDojo/blob/dev/readme-docs/KUBERNETES.md (it is the place described in the official documentation: https://documentation.defectdojo.com/getting_started/installation/#kubernetes)

README.md might point to this document as well.

[kiblik]

PR should point to dev or bugfix branch (as described in https://github.com/DefectDojo/django-DefectDojo/blob/master/readme-docs/CONTRIBUTING.md#submitting-pull-requests)

[mtesauro]

@leofvo kiblik is correct here - we only take PRs against the dev or bugfix branches. This seems like a dev branch type of PR IMHO.

[leofvo]

PR should point to dev or bugfix branch (as described in https://github.com/DefectDojo/django-DefectDojo/blob/master/readme-docs/CONTRIBUTING.md#submitting-pull-requests)

I edited to target branch as dev

[leofvo]

hey, I just merged the readme in the docs, and created a symlink to explicit the documentation location.
I did a proposal in the second commit to update the external postgresl docs as it was not really impllemented for cluster external ressources.

[mtesauro]

Approved

[hblankenship]

Minor request to change the comments on lines 443, 444 to say your database user and your database name