Fix [#137] 태스크 생성 시 startDate null 핸들링 (#138)

jaksim/src/main/java/org/sopt/jaksim/task/service/TaskService.java

@@ -46,7 +46,7 @@ public boolean isContains(TaskWithTaskTimer taskWithTaskTimer, LocalDate idxDate
     public void create(Long categoryId, TaskCreateRequest taskCreateRequest) {
         Task task = Task.create(
                 taskCreateRequest.name(),
-                taskCreateRequest.startDate(),
+                taskCreateRequest.startDate() == null ? LocalDate.now() : taskCreateRequest.startDate(),
                 taskCreateRequest.endDate());
 
         task = taskRepository.save(task);