The tag is present in Lintian version 2.104.328. That is the most recent version we know about.
The package ships a file in a location reserved for
It usually means you shipped a
Libraries should not ship Find modules Config files. Config files should
be installed in the unversioned path
When CMake Config files are installed in an unversioned path, your package will continue to work when a new version of CMake is uploaded.
Please refer to https://wiki.debian.org/CMake and https://cmake.org/cmake/help/v3.10/manual/cmake-packages.7.html#config-file-packages for details.