test: Count crashed test suites (#5924)

When outputting the unit test summary, this change counts crashed tests as failures.

src/test/unit_test/multi_runner.cpp

@@ -464,6 +464,8 @@ multi_runner_parent::~multi_runner_parent()
     continue_message_queue_ = false;
     message_queue_thread_.join();
 
+    add_failures(running_suites_.size());
+
     print_results(os_);
 
     for (auto const& s : running_suites_)