fix(content): 무료 콘텐츠 포인트 사용 조건을 보정한다

src/main/kotlin/kr/co/vividnext/sodalive/content/AudioContentService.kt

@@ -967,7 +967,7 @@ class AudioContentService(
             previousContent = previousContent,
             nextContent = nextContent,
             buyerList = buyerList,
-            isAvailableUsePoint = audioContent.isPointAvailable,
+            isAvailableUsePoint = audioContent.isPointAvailable && audioContent.price > 0,
             translated = translated
         )
     }