Prepare for using https://downloads.osmocom.org/packages/ instead of http://download.opensuse.org to download packages. Install ca-certificates before attempting to use the repository, otherwise it will print a warning and not use the repository and e.g. install eclipse-titan from debian's repository instead of our repo.
Fix for: W: https://downloads.osmocom.org/packages/osmocom:/latest/Debian_11/./InRelease: No system certificates available. Try installing ca-certificates.
