fix: ObjectMapper를 스프링 빈 주입 방법으로 수정

src/main/java/roomescape/payment/infrastructure/client/TossPaymentClient.kt

@@ -20,7 +20,8 @@ import java.util.Map
 @Component
 class TossPaymentClient(
         private val log: KLogger = KotlinLogging.logger {},
-        tossPaymentClientBuilder: RestClient.Builder
+        private val objectMapper: ObjectMapper,
+        tossPaymentClientBuilder: RestClient.Builder,
 ) {
     companion object {
         private const val CONFIRM_URL: String = "/v1/payments/confirm"
@@ -96,7 +97,6 @@ class TossPaymentClient(
             res: ClientHttpResponse
     ): TossPaymentErrorResponse {
         val body = res.body
-        val objectMapper = ObjectMapper()
         val errorResponse = objectMapper.readValue(body, TossPaymentErrorResponse::class.java)
         body.close()
         return errorResponse