chore: remove doc that was moved to the docs site

[andrablaj]

Description

Remove the documentation that was moved to the docs site to avoid duplication.

Code review checklist

• Readable: Concise, well named, follows the style guide, documented if necessary.
• Documented: Configuration and user documentation on cht-docs
• Tested: Unit and/or e2e where appropriate
• Backwards compatible: Works with existing data and configuration or includes a migration. Any breaking changes documented in the release notes.

License

The software is provided under AGPL-3.0. Contributions to this project are accepted under the same license.

[andrablaj]

@witash, this is the PR I mentioned I would open during our 1:1. Would you mind having a look? Thank you!