fix: 당일에 퀴즈를 여러번 풀 수 있는 버그를 수정한다

Author: devxb

src/main/kotlin/org/gitanimals/quiz/domain/context/QuizSolveContextService.kt

@@ -19,7 +19,7 @@ class QuizSolveContextService(
         category: Category,
         quizs: List<Quiz>,
     ): QuizSolveContext {
-        val now = LocalDate.ofInstant(instant(), ZoneId.of("UTC"))
+        val now = LocalDate.ofInstant(instant(), ZoneId.of("Asia/Seoul"))
         quizSolveContextRepository.findQuizSolveContextByUserIdAndSolvedAt(userId, now)?.let {
             throw IllegalArgumentException("Already solve daily quiz.")
         }