Rework package repo update

[Itxaka]

Creating the luet repo on a new package now takes quite a bit of time, around 20 minutes. 5 minutes downloading all the metadata in the repo and another 15 minutes checking what packages are pushed to the repo and which ones not. For the metadata makes sense that we have to download everything as we need to check against the local tree

This is mostly time consuming because for ALL the metadata it checks if the package and version is already pushed to the repo, when its clear it should be checking only packages that are on the tree but not on the repo.

Not sure if this is a luet issue, luet github action issue or we can do something on our repo. cc @mudler