feat: 题卡预览没有课程代码时隐藏条码

src/modules/card/views/CardPreview.vue

@@ -153,6 +153,9 @@ export default {
       if (detData.courseCode) {
         cardConfig.courseCodeBarcodeSrc = getBase64Barcode(detData.courseCode);
         cardConfig.courseCodeBarcodeName = detData.courseCode;
+      } else {
+        cardConfig.courseCodeBarcodeSrc = "";
+        cardConfig.courseCodeBarcodeName = "";
       }
 
       this.cardConfig = cardConfig;