Remove CACHE FORCE arguments from CMAKE_CXX_FLAG on colored terminal output
Remove CACHE FORCE arguments from CMAKE_CXX_FLAG on colored terminal output

By using CACHE STRING "" FORCE on 'set' command this updated CMAKE_CXX_FLAG
on any parent directory, thus leaking internal configuration into external
projects that may be using cucumber-cpp through add_directory.

An example is -Werror -Wall -Wextra flags set on "Generic Compiler Flags".
In a Unix + Ninja + GCC environment those flags would leak into parent
directories

cucumber/cucumber-cpp,AbletonAppDev/cucumber-cpp,AbletonAppDev/cucumber-cpp,cucumber/cucumber-cpp,meshell/cucumber-cpp,meshell/cucumber-cpp,AbletonAppDev/cucumber-cpp,meshell/cucumber-cpp,cucumber/cucumber-cpp