compiler colourful output flag leaks to fortran compiler

[LXYan2333]

though this project is mainly for cpp, I still use this for my c/fortran project and found this line:

https://github.com/cpp-best-practices/cmake_template/blob/759d7184f44aad80a3e24ba6ce8e86d08e64d9bb/cmake/StandardProjectSettings.cmake#L26

will add compile flags for fortran compiler, and if one use clang and clang++ to compile c/c++ code, and use gfortran to compile fortran code (this is allowed since the clang and gfortran can pass the FortranCInterface_VERIFY test), gfortran just complain about unknow compile flag and exit.

maybe the flags should be added for each language enabled on this project.