* Add code for DEB repository config packages.
* Add code for RPM repository config packages.
And sync up Debian related code for consistency.
* Add workflow to build and upload repoconfig packages.
* Added repoconfig repository to repoconfig packages.
This ensures we have a singe source of truth for them, and will also
make switching between stable and nightly builds much easier.
* Use base images instead of dedicated package builders.
* Don0t prompt during DEB package builds.
* Fix typos.