Add `FIND_PACKAGE_ARGS` will help `FetchContent_*` to satisfy the
dependency with `find_package()`. If that dependency is not found,
then it is built from source.

Co-authored-by: Damien Mehala <damien.mehala@datadoghq.com>

dmehala changed the title deps(nlohmann-json): avoid FetchContent if found via find_package deps(nlohmann-json): FetchContent rely on find_package

dmehala deleted the dmehala/do-not-fetch-content-nlohmann-json-if-present branch