Get rid of non-security errata html pages

[javihernandez]

The AlmaLinux Errata website contains static html pages that refer to non-security advisories, like ALEA-2021:4152. These errata html pages were generated when erratas were first introduced in AlmaLinux, and they shouldn't be there because we only publish erratas for security-related updates to packages.

In order to avoid any potential confusion in our users, we need to get rid of them.