[FIX] isLiked 필드가 null로 반환 되는 오류 (#160)

* refactor: isLiked 필드 제거

* refactor: isLiked 기본값 false 설정

* comment: 필요없는 주석 제거(반환 값 명시해주는 주석)

src/main/java/econo/buddybridge/post/dto/PostResDto.java

@@ -44,7 +44,7 @@ public PostResDto(Post post) {
                 post.getModifiedAt(),
                 post.getPostStatus(),
                 post.getDisabilityType(),
-                post.getIsLiked()
+                false
         );
     }
 

src/main/java/econo/buddybridge/post/entity/Post.java

@@ -62,8 +62,6 @@ public class Post extends BaseEntity {
     @OneToMany(mappedBy = "post", orphanRemoval = true, cascade = CascadeType.ALL)
     private final List<Comment> comments = new ArrayList<>();
 
-    private Boolean isLiked = false;
-
     public void changeStatus(PostStatus status){ // 상태 변경
         this.postStatus = status;
     }

src/main/java/econo/buddybridge/post/repository/PostRepositoryImpl.java

@@ -66,7 +66,6 @@ public PostCustomPage findPosts(Long memberId, Integer page, Integer size, Strin
                         buildPostDisabilityTypeExpression(disabilityType), buildPostAssistanceTypeExpression(assistanceType))
                 .fetchOne();
 
-        // content, totalElements, last
         return new PostCustomPage(content, totalElements, content.size() < size);
     }