Tests set their "framework" key correctly to "beakerlib", the correct setting for plan is therefore "tmt". This was not needed until recently, the old form was deprecated but still supported by Testing Farm, but not anymore.
Sanity/rebuild-kernel-and-reboot is imported from RHEL's
tests/binutils/Sanity/rebuild-kernel-and-reboot (as of commit c5bc77c).
It needs some adaptations first before running in Fedora.