[BUG] Add ghcr registry source

[bdronneau]

Describe the bug

When I add a github registry I've got

get releases for `ghcr.io/siderolabs/installer`: fetch tags: HTTP/403 Date: Thu, 05 Oct 2023 13:09:32 GMT Content-Length: 57 Content-Type: text/plain; charset=utf-8 X-Github-Request-Id: 83C5:C786:F96873:FF3E44:651EB58C {"errors":[{"code":"DENIED","message":"invalid token"}]} not found

Steps to Reproduce
Steps to reproduce the behavior:

1. Go to https://ketchup.vibioh.fr/app/#create-modal
2. Fill with ghcr.io/siderolabs/installer / stable / 1.5.3 / daily
3. Click on create
4. See error

Environment
Google chrome 117.0.5938.132 (Official Build) (arm64)

Expected behavior
Get versions from this registry

Screenshots

N/A

Additional context

akwakwak

[ViBiOh]

Hi @bdronneau,

Thanks for the submission. I had identified this issue before and I didn't addressed it yet. In fact, I'd need to provide a personnal access token to talk to GitHub, which will consume my own quota. I'll search for alternatives and if not put mine in order to unblock you.