dev 브런치 반영 code-check 오류 수정

backend/internal/repository/user_repository.go

@@ -61,7 +61,7 @@ func (r *userRepository) Update(ctx context.Context, user *domain.User) error {
 			}
 		}
 
-		// 2. Perform Upsert based on ID. 
+		// 2. Perform Upsert based on ID.
 		// In GORM v2, true upsert requires Create() with OnConflict on the primary key.
 		return tx.Clauses(clause.OnConflict{
 			Columns:   []clause.Column{{Name: "id"}},