Update sites.yml

[zkbgt]

This PR is:

• [x] Adding a new domain
• [ ] Updating existing domain size
• [ ] Changing domain name
• [ ] Removing existing domain from list
• [ ] Website code changes (512kb.club site)
• [ ] Other not listed

• [x] I used the uncompressed size of the site
• [x] I have included a link to the Cloudflare report
• [x] This site is not an ultra minimal site
• [x] The following information is filled identical to the data file

I confirm that I have read the FAQ section, particularly the two red items around minimal pages and inappropriate content and I attest that this site is neither of these things.

• [x] Check to confirm

- domain: html-chunder.neocities.org
  url: https://html-chunder.neocities.org/
  size: 54.1
  last_checked: 2024-09-28

Cloudflare Report: https://radar.cloudflare.com/scan/9d5ec18b-5213-48ee-86b8-4a9dbff14e87/summary