[knot-resolver-users] debian repo: http -> https

The instructions on: https://www.knot-resolver.cz/download/ read: " wget https://secure.nic.cz/files/knot-resolver/knot-resolver-release.deb dpkg -i knot-resolver-release.deb apt update && apt install -y knot-resolver " these instructions result in an http://.. URL in: /etc/apt/sources.list.d/knot-resolver-latest.list I'd suggest to change it to https://..