Source for ccnet-dbg and libccnet-dbg
The package libccnet-dbg is not available for any release of Ubuntu - https://packages.ubuntu.com/search?keywords=libccnet-dbg&searchon=names&suite=all§ion=all
Providing the instructions you're following, as Lubuntu/Ubuntu documentation makes no mention of it.
https://packages.ubuntu.com/bionic/libdevel/libccnet-dev maybe closest; but I'd want to know what instructions you're following; that was removed as it relied on python2 which is EOL for a start.
Another significant problem was that the upstream repository was deleted; refer https://tracker.debian.org/pkg/ccnet