Why you are renaming file zconf.h to zconf.h.included in source files? (CMakeLists.txt:77)
It is making the git revision as dirty and force users to fetch your code to build directory instead to use it as a git submodule.
I see that you already have file zconf.h.in, so why you are not using configre_file function to generate zconf.h in build directory. Then only you need to do is to add target_include_directories(${PROJECT_NAME} PUBLIC ${CMAKE_CURRENT_BINARY_DIR}). zconf.h shall then be also be removed from source code.
Please consider it ASAP