refactor: isNotWriter 메서드 제거

Author: leebs0521

src/main/java/com/somemore/recruitboard/domain/RecruitBoard.java

@@ -73,10 +73,6 @@ public boolean isWriter(UUID centerId) {
         return this.centerId.equals(centerId);
     }
 
-    public boolean isNotWriter(UUID centerId) {
-        return !isWriter(centerId);
-    }
-
     public void updateWith(RecruitBoardUpdateRequestDto dto, String imgUrl) {
         updateVolunteerInfo(dto);
         this.title = dto.title();

src/main/java/com/somemore/recruitboard/service/command/UpdateRecruitBoardService.java

@@ -59,8 +59,10 @@ public void updateRecruitBoardLocation(RecruitBoardLocationUpdateRequestDto requ
     }
 
     private void validateWriter(RecruitBoard recruitBoard, UUID centerId) {
-        if (recruitBoard.isNotWriter(centerId)) {
-            throw new BadRequestException(UNAUTHORIZED_RECRUIT_BOARD.getMessage());
+        if (recruitBoard.isWriter(centerId)) {
+            return;
         }
+
+        throw new BadRequestException(UNAUTHORIZED_RECRUIT_BOARD.getMessage());
     }
 }