Update burgmann.json to use Cloudflare NS

[franzbu]

Requirements

• I agree to the Terms of Service.
• My file is following the domain structure.
• My website is reachable and completed.
• My website is software development related.
• My website is not for commercial use.
• I have provided contact information in the owner key.
• I have provided a preview of my website below.

Website Preview

https://burgmann.is-a.dev (currently routing to https://franzbu.github.io)

Website Purpose

This is my personal developer portfolio and project portal. I am updating my registration file to delegate NS records to Cloudflare for advanced routing.

[is-a-dev-reviewbot]

Hi there! 👋

You've successfully made a pull request! Here are some steps to do while waiting for a maintainer to review the pull request:

1. Check if the checks have failed or passed. You should see the status at the bottom of the pull request or a icon next to the commit ID. You can click on the 3 dots next to the "CI / Tests" check then click "View details", it will show you the logs of the tests.
2. Check if the filename, file format, and records are valid. If you don't know if it's valid, please read this part of the documentation and use a JSON validator/formatter, like jsonlint. Make sure that the file is in the domains directory and not somewhere else in the repository.
3. Please make sure that you've filled out the pull request template. It is generally not a good idea to overwrite the pull request template with something else unless you know what you are doing. Make sure to add either a publicly available preview of your website or a screenshot of it.
4. Please wait patiently. Pull requests may take between a couple hours to 3 days. All of the maintainer team are volunteers and try to review the pull requests in their spare time. If you want a chance of getting your pull request merged faster then send your pull request number once in the #pull-requests channel in our Discord server and wait patiently.
5. Please note that mentioning maintainers in pull requests without it being reviewed could lead to you getting marked as "low priority"; this also applies to pinging the maintainers in the Discord server or messaging the maintainers in private to review the pull request.

Note: if you've opened this pull request while there is a high number of other open pull requests, your wait time will be longer than usual. Please be patient!

[github-actions]

This pull request has been marked as stale due to inactivity and will be closed. Comment anything on this PR to prevent it