public function testWorkingDayCanDeleteATaskWithDescription()
 {
     $task = new Task("Task day.");
     $task2 = new Task("Task 2 day.");
     $this->workingDay->addTask($task);
     $this->workingDay->addTask($task2);
     $this->workingDay->deleteTaskWithDescription(new TaskDescription('Task 2 day.'));
     $this->assertCount(1, $this->workingDay->getTasks());
 }