CLAP-70 Fix: untilDate 파라미터가 null일 경우 처리

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- 관련: #29

Author: joowojr

src/main/java/clap/server/application/Task/TaskBoardService.java

@@ -1,6 +1,5 @@
 package clap.server.application.Task;
 
-import clap.server.adapter.inbound.web.dto.task.request.UpdateTaskOrderRequest;
 import clap.server.adapter.inbound.web.dto.task.response.TaskBoardResponse;
 import clap.server.adapter.outbound.persistense.entity.task.constant.TaskStatus;
 import clap.server.application.mapper.TaskMapper;
@@ -10,7 +9,6 @@
 import clap.server.application.port.outbound.task.CommandTaskPort;
 import clap.server.application.port.outbound.task.LoadTaskPort;
 import clap.server.common.annotation.architecture.ApplicationService;
-import clap.server.domain.model.member.Member;
 import clap.server.domain.model.task.Task;
 import lombok.RequiredArgsConstructor;
 import org.springframework.data.domain.Pageable;