This PR creates the necessary CI infrastructure to copy `.deb` packages
from releases to our APT repository. Re-generation of the index is
separated out into a dedicated workflow to avoid concurrency issues and
so we can re-generate it without making a release.
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Signed-off-by: Thomas Eizinger <thomas@eizinger.io>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
