manager: initialize timeouts when allocating a naked Manager object

This way we can safely run manager objects from tests and good timeouts
apply. Without this all timeouts are set 0, which means they fire
instantly, when run from tests which do not explicitly configure them
(the way main.c does).

src/core/manager.c

@@ -616,6 +616,9 @@ int manager_new(UnitFileScope scope, unsigned test_run_flags, Manager **_m) {
         m->default_timer_accuracy_usec = USEC_PER_MINUTE;
         m->default_tasks_accounting = true;
         m->default_tasks_max = UINT64_MAX;
+        m->default_timeout_start_usec = DEFAULT_TIMEOUT_USEC;
+        m->default_timeout_stop_usec = DEFAULT_TIMEOUT_USEC;
+        m->default_restart_usec = DEFAULT_RESTART_USEC;
 
 #ifdef ENABLE_EFI
         if (MANAGER_IS_SYSTEM(m) && detect_container() <= 0)