Function get_thread_id_as_string

src/tests/rpp/test_scheduler.cpp:36–41

using namespace std::string_literals;

static std::string get_thread_id_as_string(std::thread::id id = std::this_thread::get_id())
{
    std::stringstream ss;
    ss << id;
    return ss.str();
}

static std::string simulate_nested_scheduling(auto worker, const auto& obs, std::vector<std::string>& out)
{